Open Collections

UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

First year performance and root egress of white spruce (Picea glauca (Moench) Voss) and lodgepole pine… Von der Gonna, Marc A. 1989

Your browser doesn't seem to have a PDF viewer, please download the PDF to view this item.

Item Metadata

Download

Media
831-UBC_1989_A6 G66.pdf [ 6.96MB ]
Metadata
JSON: 831-1.0097403.json
JSON-LD: 831-1.0097403-ld.json
RDF/XML (Pretty): 831-1.0097403-rdf.xml
RDF/JSON: 831-1.0097403-rdf.json
Turtle: 831-1.0097403-turtle.txt
N-Triples: 831-1.0097403-rdf-ntriples.txt
Original Record: 831-1.0097403-source.json
Full Text
831-1.0097403-fulltext.txt
Citation
831-1.0097403.ris

Full Text

FIRST YEAR PERFORMANCE AND ROOT EGRESS OF WHITE SPRUCE (PICEA GLAUCA (MOENCH) VOSS) AND LODGEPOLE PINE (PINUS CONTORTA DOUGL.) SEEDLINGS IN MECHANICALLY PREPARED AND UNTREATED PLANTING SPOTS IN NORTH CENTRAL BRITISH COLUMBIA. by MARC A. VON DER GONNA B.Sc.F., Forestry, U n i v e r s i t y of Toronto, 1986 A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF FORESTRY i n THE FACULTY OF GRADUATE STUDIES (Department of Forestry) we accept t h i s t h e s i s as conforming to the required standard. THE UNIVERSITY OF BRITISH COLUMBIA January 1989 © Marc A. von der Gonna, 1989 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of F o r e s t r y The University of British Columbia Vancouver, Canada Date A p r i l 18, 1989  DE-6 (2/88) F i r s t year performance and root egress of white spruce (Picea glauca (Moench) Voss) and lodgepole pine (Pinus contorta Dougl.) seedlings i n mechanically prepared and untreated p l a n t i n g spots i n north c e n t r a l B r i t i s h Columbia. Abstract Root zone temperature and root egress were studied during the f i r s t growing season on white spruce and lodgepole pine seedlings planted i n various forms of mechanically prepared m i c r o s i t e s . Mounded mic r o s i t e s had higher summer s o i l temperatures and greater d i u r n a l ranges, at a depth of 10 cm, than the patch and c o n t r o l treatments. Mounded m i c r o s i t e s , however, showed the greatest response to changes i n weather and decreasing s o l a r r a d i a t i o n inputs i n the f a l l , being the f i r s t to record s o i l temperatures below f r e e z i n g . Seedlings planted i n the deep mineral s o i l over i n v e r t e d humus mounds created by the M i n i s t r y Mounder had s i g n i f i c a n t l y greater numbers of new roots greater than 1 cm long than d i d seedlings planted i n patch and c o n t r o l treatments at 45 and 70 days a f t e r p l a n t i n g . Seedlings planted i n other mound and plowing treatments had high to intermediate numbers of new roots. At 95 days a f t e r p l a n t i n g , seedlings planted on a l l mounded treatments g e n e r a l l y had higher root area i n d i c e s , root dry weights and t o t a l dry weights than d i d seedlings on other treatments. V a r i a t i o n i n treatment r e s u l t s over the three spruce s i t e s studied r e f l e c t d i f f e r e n c e s i n s i t e c onditions, p r i m a r i l y s o i l moisture regimes. High and f l u c t u a t i n g water tables n e g a t i v e l y a f f e c t e d seedlings planted i n patch and c o n t r o l treatments. Table of Contents i i i page Abstract i i Table of Contents i i i L i s t of Tables v i L i s t of Figures v i i L i s t of Appendices i x L i s t of Abbreviations x Acknowledgements x i 1 Introduction 1 1.1 L i t e r a t u r e Review 4 1.1.1 Introduction 4 1.1.2 S i t e preparation and seedl i n g growth and s u r v i v a l 4 1.1.3 S i t e preparation and m i c r o s i t e conditions 8 1.1.4 M i c r o s i t e conditions and seedl i n g response 13 1.1.4.1 S o i l temperature 13 1.1.4.2 S o i l moisture 22 1.1.5 Summary 27 1.2 Objectives 29 2 Ma t e r i a l s and methods 30 2.1 S i t e s e l e c t i o n 30 2.2 S i t e d e s c r i p t i o n 30 i v page 2.2.1 Iron Creek 30 2.2.2 Stewart Lake 33 2.2.3 Mackenzie 33 2.2.4 Kluskus Road 33 2.3 Experimental layout 34 2.4 S i t e preparation treatments 34 2.4.1 The M i n i s t r y Mounder 38 2.4.2 The Sinkkila" HMF Scarifier/Mounder 38 2.4.3 The Bracke Mounder/Patch S c a r i f i e r 39 2.4.4 The Breaking plow 40 2.4.5 The V-blade 40 2.4.6 The Donaren 180 40 2.4.7 Untreated c o n t r o l 41 2.5 P l a n t i n g stock 41 2.6 P l a n t i n g 42 2.7 B i o l o g i c a l assessment 44 2.8 Ana l y s i s 48 2.9 Environmental monitoring study 48 2.10 Vegetation ingrowth assessment 48 2.11 S u r v i v a l and f r o s t damage 49 3 Results 50 3.1 F i e l d assessment of mound c o n f i g u r a t i o n 50 3.2 Environmental monitoring 50 3.2.1 Root zone temperatures 51 3.3 B i o l o g i c a l 54 3.3.1 Root growth 56 page 3.3.2 Shoot growth 67 3.3.3 F o l i a r a n a l y s i s 70 3.3.4 S u r v i v a l and f r o s t damage 70 3.4 Vegetation ingrowth and competition 73 4 Discussion 75 4.1 Microclimate 75 4.2 Root egress 78 4.3 Seedling growth response 81 4.4 Subsequent 1988 observations 82 4.5 Weaknesses of the study 84 5 Conclusions 85 6 P r a c t i c a l a p p l i c a t i o n s 86 Bibliography 87 Appendices 92 L i s t of Tables Table 1. C h a r a c t e r i s t i c s of treatment s i t e s . 2. Summary of seedl i n g stock information. 3. Summary of morphological measurements and RGC t e s t i n g . 4. P l a n t i n g dates by s i t e . 5. Treatments studied and sampling i n t e n s i t y at each l o c a t i o n . 6. Summary of performance of the three mounding implements. 7. Mean number of new roots growing from the root plug, 45 days a f t e r p l a n t i n g . 8. Mean number of new roots growing from the root plug, 70 days a f t e r p l a n t i n g . 9. Mean root area i n d i c e s , 95 days a f t e r p l a n t i n g . 10. Summary of se e d l i n g dry weight data, 95 days a f t e r p l a n t i n g . 11. Summary of seedl i n g growth data, 95 days a f t e r p l a n t i n g . 12. F o l i a r a n a l y s i s of 1987 leader growth, 95 days a f t e r p l a n t i n g . 13. Summary of s u r v i v a l and f r o s t damage at the end of the f i r s t growing season. 14. Summary of the assessment of vegetation ingrowth and competition. L i s t of Figures Figure 1. Location of study s i t e s . 2. P l o t layout and assignment of treatments, Iron Creek s i t e . 3. P l o t layout and assignment of treatments, Stewart Lake s i t e . 4. Ploy layout and assignment of treatments, Mackenzie s i t e . 5. Ploy layout and assignment of treatments, Kluskus Road s i t e . 6. Diagram of treatment m i c r o s i t e s and p l a n t i n g p o s i t i o n s . 7. Diagram showing how the t a l l y of root egress was broken i n t o groups. 8. Schematic diagram of root box, video system, and area meter used to measure root area index. 9. P l o t s of s o l a r r a d i a t i o n , p r e c i p i t a t i o n , a i r temperature, and root zone temperature i n a mound mic r o s i t e , monitored on the Iron Creek s i t e . 10. Root egress 45 days a f t e r p l a n t i n g , Iron Creek s i t e . 11. Root egress 45 days a f t e r p l a n t i n g , Stewart Lake s i t e . V l l l page 12. Root egress 45 days a f t e r p l a n t i n g , Mackenzie s i t e . 59 13. Root egress 70 days a f t e r p l a n t i n g , i r o n Creek s i t e . 61 14. Root egress 70 days a f t e r p l a n t i n g , Stewart Lake s i t e . 61 15. Root egress 70 days a f t e r p l a n t i n g , Mackenzie s i t e . 62 16. Root egress 70 days a f t e r p l a n t i n g , Kluskus Road s i t e . 62 17. T o t a l degree hours greater than 10 degrees C recorded at a depth of 10 cm i n hygric, subhygric and mesic p l o t s , by Macadam (1988). 76 i x L i s t of Appendices page Appendix A S o i l texture and humus depth/form. 92 Appendix B F i e l d assessment of i n v e r t e d humus mounds. 106 Appendix C Results of the environmental monitoring p r o j e c t (FRDA 1.25). 115 L i s t of Abbreviation RGC n/a LT GT min. m. bracke m. br. plow sink. m. D-180 N cone. P cone. UNTRT LG INV MND SML INV MND MIN MND x Abbreviations F u l l Text root growth capacity data not a v a i l a b l e l e s s than greater than M i n i s t r y mounder Bracke mounder breaking plow S i n k k i l a mounder Donaren 180 f o l i a r N concentration f o l i a r P concentration untreated c o n t r o l large i n v e r t e d mound small i n v e r t e d mound mineral s o i l mound x i Acknowledgement s The research was funded under the Canada - Bri t i s h Columbia Forest Resource Development Agreement (FRDA). The author is grateful for the assistance provided by the Natural Science and Engineering Research Council of Canada. The author is grateful for the assistance, guidance and support provided by Dr. D.P. Lavender (Prof, and Head, Dept. For. Sci., UBC); the cooperation of L.R. Bedford (FRDA 1.10 Project Leader), A. McLeod and M. Osberg (FRDA 1.25 Project Leaders), S. Jenvey (Contractor), D. Draper and Staff, Red Rock Research Station, S. and J. Zimonic (planting contractors), and R.G. McMinn (Consultant). The author also wishes to thank his committee, Dr.'s Lester, Weetman, Guy, Grossnickle and Lavender, and I. Hedin (FERIC) for their c r i t i c a l review of this manuscript. 1 1 Introduction Backlog NSR (Not Satisfactorily Restocked land) is a major problem in the northern interior of B r i t i s h Columbia. Failure of conifer plantations, primarily white spruce, has been most common on wetter, brush-prone eco-systems . Low s o i l temperature and vegetation competition have been cited as the major cause of these plantation failures (Butt 1986, Macadam 1986, McMinn 1982). Butt (1986) stated that " i t was generally understood that slow warming of the mineral s o i l in the early summer restricted root egress of both white spruce and lodgepole pine, and therefore contributed to 'growth check' and/or poor performance". Dobbs (1972) reported that white spruce i s well known to exhibit 'planting check' whereby the growth of the out-planted seedlings i s n i l or exceedingly slow, and that check was found to reduce leader length by about 50% in the f i r s t year after outplanting and have some negative effect for 10 years or more. Burdett et a l . (1984) stated that planting check of one or several seasons has l i t t l e direct effect on planta-tion productivity. Indirectly, however, planting check can have a major impact on y i e l d by putting stock at a disadvantage in the competition with other vegetation. In his report to the Ministry of Forests and Lands (now Ministry of Forests, MOF), Butt (1986) stated that as of October 31, 1986 just under 500,000 ha were c l a s s i f i e d as NSR in the northern interior, with about 70 percent or 345,166 ha located in the Sub-Boreal Spruce (SBS) zone and 144,088 ha in the Boreal White and Black Spruce (BWBS) zone. Mechanical site preparation w i l l play an important role in the rehabilitation of these sites (Bedford 1986). Mechanical site preparation treatments to rehabilitate backlog areas for planting must be site specific. Prescription decisions can be assisted by 2 the use of ecological c l a s s i f i c a t i o n systems (Corns 1984, Corns and Annas 1984, Stahl 1984). Coates and Haeussler (1984) present such a handbook to assist f i e l d s i l v i c u l t u r i s t s in north central B r i t i s h Columbia in making ecologically-based prescriptions for mechanical site preparation treatments. The guide, based on the British Columbia biogeoclimatic zone c l a s s i f i c a t i o n system, describes 15 types of mechanical site preparation equipment. It contains comparisons of equipment capabilities based on physical site factors and a section on ecosystem interpretation. Such a guide, however, needs continuous, ongoing updating as experience is gained and new treatments and implements are tested. A second edition (MacKinnon et a l . 1987) has already been printed. The need for a standardized, systematic approach to equipment assessment is crucial i f v a l i d comparisons are to be made, but only recently has a standard procedure been introduced and used (Sutherland 1986). The need for follow-up biological assessment is obvious (Sutherland 1987) . Bedford (1986) states that "while the biological effectiveness of machines for preparing planting spots can be judged on the basis of experience, the measurement of seedling performance under comparable conditions i s needed to verify such judgements". Smith (1984) reviews the history of mechanical site preparation development in Canada, and states that "biological research i s generally long-term in nature and i s often preceded by technical advance-ment" . Under the Canada-British Columbia Forest Resource Development Agreement (FRDA) 1985-90 Backlog Reforestation Program, a project was undertaken to test the operational and biological effectiveness of current site preparation equipment (FRDA Project 1.10) . Objectives of the program are: 1) to evaluate the relative operational and biological effectiveness of site preparation machines for backlog rehabilitation; 2) to assist where appropriate in the modification of existing site preparation equipment and systems; and, 3) to assist where appropriate the development of promising new site preparation machines or systems. Ecosystem association and s o i l type were identified as part of site selec-tion, and comparative plots have been established in several different years to discount year-to- year climate differences and stock variation (Bedford 1986). As part of the i n i t i a l assessment of the biological effectiveness of the various treatments a study on root egress was mounted (FRDA 1.24, von der Gonna and Lavender 1987). This thesis presents a summary of the f i r s t year results of this study. 4 1.1 Literature Review 1.1.1 Introduction Mechanical site preparation is one treatment forest managers can use to effect the establishment, survival and early growth of plantation seedlings. The favourable response of seedlings to various forms of mechanical site preparation has been shown in numerous t r i a l s throughout the boreal forest and has been documented by many authors (Hunt 1987). Mechanical site preparation affects seedling growth by altering the planting microsite. Various studies have monitored changes in s o i l tempera-ture and moisture regimes as a result of mechanical site preparation treat-ments (Ballard et a l . 1977, Orlander 1986, Herring and Letchford 1987, Spittlehouse 1988, Macadam 1988). These changes are specific to each treatment and are the result of changes made to various s o i l properties. Plant physiologists have studied seedling response to various microsite conditions. Cold s o i l temperature has been shown to affect seedling root growth, water potential, stomatal conductance, and nutrient uptake. The effects of s o i l moisture, various depths of water table, and periods of flooding on seedling physiology have also been studied. 1.1.2 Site Preparation and Seedling Growth and Survival Mechanical site preparation to alter the planting microsite has been shown to improve seedling root growth, establishment, and performance. Much of the pioneering work in site preparation research has been carried out in Scandinavia. Edlund (1979) reported on the increased interest in mounding treatments in Sweden during the 1970's. One year old container lodgepole pine seedlings 5 were planted on deep patch, mineral mound, humus mound, scarified patch, and untreated microsites. Results after 2 growing seasons showed significantly higher survival of a l l treatments over no treatment and greatest leader growth and total seedling height in the humus mound treatment. Edlund and Jonsson (1986) reported the results of mounding t r i a l s established in the mid-1970's in Sweden. Results of Pinus contorta and Pinus s y l v e s t r i s plantations show mounding to produce trees 50% t a l l e r on the average than patch treatments 6 to 9 years after planting. Soderstrom (1981) reported the results of t r i a l s of 2-0 bare-root Pinus sylvestris seedlings, planted in unscarified, patch and patch scarified/heap microsites in Sweden. The number of non-lignified white roots 35 days after planting was over twelvefold and sixfol d that of unscarified seedlings for patch/heap and patch seedlings, respectively. Height growth was similar for patch and patch/heap seedlings 7 growing seasons after planting, but survival was only 55% for patch seedlings compared with 90% for patch/heap seedlings. Similar studies conducted i n Canada have shown comparable results. On sandy soils in Ontario, Armson (1958) reported better growth of white spruce in plowed ridges. Sutton (1984) reported on t r i a l s of manually-created mineral s o i l over inverted humus mounds on well-drained coarse textured s o i l s , typical of jack pine sites in Ontario. He found that patch scarification generally gave better survival and height development than mounds. Diameter increment was promoted in mounds in some cases. Seedlings on mineral s o i l mounds with intact capillary contact fared better than seedlings on mineral s o i l on inverted humus mounds. Van Damme (1987) reported on t r i a l s in which bare-root planted black spruce and jack pine were tested for their growth response to manually 6 mounded Bracke microsites across seven locations in north western Ontario, over three years. Assessments five years after planting showed pine responded favourably to mound treatments with increased basal diameters and related tree volume; however, height growth differences were very small. Pine showed high levels of mortality on inverted humus mounds in one replica-tion. Spruce showed very limited response to microsite effects, possibly due to i t s small size or large ecological amplitude. Planting either species i n the bottom of the patch resulted in poor growth, similar to unscarified ground. McMinn (1982) reported on the performance of planted white spruce in Bri t i s h Columbia, in t r i a l s established on sites with high potential for competing vegetation. In medium- to moderately coarse-textured s o i l s , where root growth was not impeded by compact subsurface s o i l structure, scalping increased root-zone s o i l temperature, more than compensating for the reduc-tion i n s o i l f e r t i l i t y . On a site with a gravelly loam s o i l and high vegetation competition, scalped spots were superior to no treatment, but were poorer than spots formed by blade scarification. Patch size and trench width appeared to be too small to adequately protect seedlings .from adverse effects of competing vegetation. Results from a wet site showed that even the sloping margins of scalped patches were unsatisfactory for seedling survival and growth. Performance of seedlings planted on mounds formed by material dug from scalped patches was better despite greater vegetation competition on these mounds compared to the scalped hollows. McMinn (1985a) stated that "judicious mechanical site preparation can produce impressive improvement in survival and growth of interior spruce seedlings. Each of three basic methods, screefing, mixing, and inverting, may be biologically satisfactory under appropriate site conditions." Results 7 10 years after planting showed that mixing, which incorporated surface organic matter into the subsurface mineral s o i l , increased seedling growth over no treatment. Seedlings planted in inverted patches were found to grow faster than seedlings i n screefed areas. McMinn (1985b) tested the effect of various depths of mineral s o i l cappings on the performance of white spruce seedlings planted in inverted humus mounds. Four years after planting seedling survival was lowest in untreated areas but did not d i f f e r among the mound types or between mounds and blade sc a r i f i e d areas. Stem volumes calculated from annual height and diameter measurements showed that seedlings grow best in mounds with the deepest mineral s o i l capping. Seedling growth in mounds with a l l depths of capping was better than in blade scarified and untreated areas. The mass of fine roots (less than 1 mm in diameter) of sample seedlings excavated at the end of the second growing season was likewise greatest for seedlings in mounds with the deepest capping. Seedlings in untreated areas had l i t t l e root growth. The biological goals of site preparation must be defined, however, i f successful results are to be achieved. These goals can vary based on different site and s o i l conditions. McMinn (1982) stated that "appropriate site preparation methods can ameliorate factors adversely affecting seedling survival and growth, however, prescriptions must be site specific because site factors unfavourable in one ecosystem may be satisfactory in others". Sutton (1975) warned that "the biological aspects of s i l v i c u l t u r e are a l l - . pervading, and they determine not only what is possible but how readily i t may be achieved". 8 1.1.3 Site Preparation and Microsite'Conditions Mechanical site preparation treatments affect seedling performance by changing various properties of the planting microsite to meet seedling requirements. Factors limiting seedling growth on one site may not be limiting on another, therefore, treatments must be site specific and the limiting factors identified before treatment prescription. Fryk (1986) explained how one management system, based on this principle, could be applied to treatment prescription i n Sweden. In adopting this adapted site preparation management system i t is i n i t i a l l y necessary to define the biological requirements desired under various site conditions, and then c l a r i f y what kind of microclimate condition there is to be expected from different site preparation treatments. Important site properties one must consider are temperature and precipitation climate, water supply, and a v a i l a b i l i t y of nutrients. Of a l l the seedlings' requirements, Fryk (1986) stated that s o i l moisture and s o i l temperature are the most important during the establishment phase. Mechanical site preparation has been shown to alter s o i l temperature regimes by altering microsite s o i l properties. McMinn (1985b) reported that f i e l d studies in which s o i l temperatures have been monitored over a range of mechanical site preparation treatments have shown that exposure of mineral s o i l by scalping, plowing, mixing or mounding can significantly increase s o i l root zone temperature over no treatment. The extent of the effect i s limited by the amount and depth of s o i l moisture (Ballard et a l . 1977), and mounding or plowing are particularly effective where a high, or periodically high water table causes patches to remain relatively cool (McMinn 1982, Hunt 1987). 9 Ballard et a l . (1977) measured summer daytime energy balances and temperature profiles at three clearcut surfaces: slashburned, exposed mineral s o i l , and undisturbed forest floor. Exposure of mineral s o i l increased s o i l and latent heat fluxes and decreased sensible heat flux. Surface temperature was lowest and temperature at a depth of 30 cm was highest where mineral s o i l was exposed, primarily effected by increases in thermal admittance and d i f f u s i v i t y , respectively, of material near the surface. Herring and Letchford (1987) summarized the important thermal properties of the s o i l as follows. Heat capacity i s the amount of heat required to raise the temperature of 1 cc of s o i l material by 1 degree C and i t increases with increasing moisture content. Thermal conductivity i s the amount of heat flowing per unit time through a unit area of unit thickness with a unit temperature difference. It increases with decreasing porosity, increasing moisture content, and decreasing organic matter content. The ratio of thermal conductivity to heat capacity indicates the f a c i l i t y with which a s o i l w i l l undergo a temperature change and is called the thermal d i f f u s i v i t y . Surface heat i s transmitted downward in waves which decrease in amplitude with s o i l depth. The effects of incoming solar radiation on s o i l temperature can be altered by a surface insulating layer such as a mulch or vegetation; by changing the absorptivity of the surface; or, by changing the d i f f u s i v i t y . Also, the l i t t e r layer acts as an insulating mulch resulting in lower s o i l temperatures beneath. A mineral s o i l surface, although having a lower absorptivity, w i l l have a higher d i f f u s i v i t y , i f not too porous, and w i l l generate warmer temperatures below the surface. Herring and Letchford (1987) monitored s o i l temperature at 5, 15 and 30 cm depths, for three years, as part of a major backlog rehabilitation project, 50 km west of Dawson Creek, B r i t i s h Columbia. Temperature differences observed were attributed to differences in the thermal properties of the s o i l as affected by each treatment. Summer temperature regimes were rationalized by examining the characteristics of the site treatments. I n i t i a l l y the plowing treatment recorded the highest temperatures, followed by discing, f a l l clearing, and winter clearing, respectively, i n descending order. As temperatures warmed during the summer the ranking was maintained and enhanced. An isothermal period in the f a l l was followed by winter temperatures in the reverse order. The absence of a surface organic layer distinguished plowed plots from the others. Plowing enabled the sun's energy to directly reach the mineral s o i l without losses due to the insulating effect of organic matter and vegetation. Unless s o i l moisture i s excessive, plowed plots w i l l be the warmest throughout the summer months. However, this treatment w i l l also show the greatest fluctuation in temperature response to weather changes as was shown by comparison with the a i r temperature observations. Plowing also changed the microtopography of the site by introducing improved drainage and increasing the surface area of the mineral s o i l . This lat t e r effect, however, increased night- time radiation, thereby more rapidly lowering s o i l temperature. Similarly, in the late summer plowed sites w i l l cool more rapidly as radiation input declines. Winter sheared plots were the coolest because the organic layer was v i r t u a l l y intact and the s o i l surface was shaded by vegetation. F a l l clearing and discing treatments were quite similar, but the additional disturbance of the discing action permitted more warm a i r and radiation to penetrate the s o i l surface, thereby allowing disced plots to warm further. Spittlehouse (1988) presented data summaries of continuously monitored s o i l and atmosphere conditions from summer 1983 to winter 1986/87, for a variety of microsite treatments. Soil temperature was continually measured at the 0.005, 0.05, 0.1, 0.2 and 0.5 m depth in 1984, and at 0.005, 0.1 and 0.2 m depths in 1985 and 1986. At the time of planting in 1984, the mound and organic mat treatments averaged 5 to 7 degrees C, while the control treatments averaged 4 to 5 degrees C. After planting the mounds and mat rapidly warmed in the p a r t i a l l y cloudy conditions, reaching an average temperature of 10 degrees C at 0.1 m by June 5. The diurnal range was 5 to 10 degrees C. The controls averaged only 6 to 7 degrees C at this time with a diurnal range of 1 to 2 degrees C. By late June, daily 0.1m temperature i n the mound treatment was varying from a maximum of over 20 degrees C to a minimum of about 9 degrees C. Similar temperatures were obtained in the organic mat treatments, while the diurnal swing in the control treatment was in the order of 1 degree C. The 0.005 and 0.1m temperatures averaged, respectively, 10 and 7 degrees C greater i n the mound than the control. The 0.1m temperatures in the controls reached an average of 10 degrees C on July 2 6, 41 days after the mounds. The 0.2 m temperatures in the control lagged that of the 0.1m and did not reach 10 degrees C u n t i l August 10. At this time the mound 0.2 m average temperature was 16 degrees C. Soil temperatures started to decrease in mid August. By late September, the average temperature in the top 0.2 m of the mound, mat and control treatments had dropped to 5 degrees C. This resulted in total growing degree days (5 degrees C base) of 860, 800 and 470 in the mound, mat and control treatments, respectively. The mound s o i l temperatures reached 0 degrees C on October 18. The control treatment was at 2 degrees C. Conditions similar to those in 1984 prevailed during 1985 and 1986. The increase in shading of the mound and organic mat treatments had somewhat reduced their temperatures in mid-summer, however, they s t i l l averaged 3 to 6 degrees C above the temperatures in the control treatment. A comparison of the s o i l temperatures at 0.1 m in the various sizes of mounds and other treatments was made in 1985 and 1986. Increased temperatures at 0.1 m were found with increased mound size. Similar temperature regime patterns of other comparative site prepara-tion t r i a l s have been reported by Macadam (1988) and Orlander (1986). Macadam (1988) monitored s o i l temperature, 10 cm from the s o i l surface, hourly from late May to late October, 1987, in manually created mounding, plowing, and scalping treatments on mesic, subhygric, and hygric portions of an area in north central B r i t i s h Columbia. Inverted mounds consistently exhibited the most extreme differences between night and day temperatures i n a l l site types, followed by mineral mounds, plowed, scalped, and untreated spots. For July the diurnal variation in hygric plots averaged 12 degrees C for small inverted mounds and 2 degrees C for untreated spots. From late May to early September in the hygric plot, minimum temperatures in the inverted mounds generally remained higher than those recorded in untreated and scalped spots and from September to October 31, minimum temperatures were similar in a l l treatments within 1 - 2 degrees C. Inverted mounds in the mesic plots tended to be more responsive to low a i r temperatures. From September to October daily minima were consistently lower in mounds and by October 8 had dropped below 0 degrees C, followed closely by mineral mounds and plowed spots, while scalped and untreated spots remained above 1 degree .C and 2 degrees C, respectively up to the end of October. Summed, degree hours for seedling root zone temperatures greater than 10 degrees C showed significant treatment differences, and were summarized in four distinct periods: 1) an 'early' phase from mid-May to June 24, during which only the mounded treatments achieved the base temperature for significant periods; 2) a 'warm' phase from June 25 to August 9, during which to t a l degree hours greater than 10 degrees C were at a maximum for a l l treatments and the differences among treatments the greatest; 3) a 'late' phase from August 10 to September 9, during which to t a l degree hours declined from maximum but remained higher than 'early' phase levels and significant differences among treatments persisted; and, 4) a 'post-growing-season' phase beginning September 10, after which the occurrence of temperatures greater than 10 degrees C declined substan-t i a l l y in a l l treatments and differences among treatments diminished sharply. As Fryk (1986) explained, we can use the knowledge that mechanical site preparation can affect root zone s o i l temperature and moisture positively, only i f we know how these factors limit seedling performance. 1.1.4 Microsite Conditions and Seedling Response 1.1.4.1 Soil Temperature Many lab studies have shown that low s o i l temperature negatively affects conifer seedling root growth. Carlson (1986) used bare-root, one-year old l o b l o l l y pine seedlings in a variety of pot tests to emphasize the importance of the root system to seedling performance. Hydraulic conductivity was affected by root volume prior to new root growth and was even more strongly affected by new root growth, presumably due to unsuberized roots being more conductive than suberized roots. Root growth in the f i e l d was found to follow the rise in temperature. Potted seedlings with s o i l temperatures held at 10, 15 and 20 degrees C showed the greatest numbers of new roots greater than 1 cm at 20 degrees C, after 28 days. Root growth was minimal at 10 degrees C. Seedling establishment was separated into three phases: 1) post-planting but preroot-elongation, in which the seedling i s dependent on the planted root system for water and nutrient uptake; 2) rapid root development, which begins when s o i l temperatures exceed 10 degrees C; and, 3) rapid shoot elongation and leaf area expansion, which i s a function of environmental conditions, but may be delayed i f moisture stress accumu-lates over phases 1 and 2. Andersen et a l . (1986) grew two-year old red pine seedlings in pots with s o i l temperatures maintained at 8, 12, 16, and 20 degrees C for 27 days. Root t i p i n i t i a t i o n was i n i t i a l l y slowed by temperatures below 20 degrees C, but after 4 weeks, the total number of roots i n i t i a t e d was similar for 12, 16 and 20 degrees C. After 27 days, seedlings at 16 degrees C produced the greatest number of new root tips, while seedlings at 8, 12 and 20 degrees C did not d i f f e r significantly. The decrease in to t a l number of new root tips from 16 to 20 degrees C may reflect increased u t i l i z a t i o n of carbohydrates for elongation at the expense of new t i p development at 20 degrees C. Root elongation increased with increasing temperature with the greatest number of new roots 0.5 cm and longer at 20 degrees C, at a l l sampling dates. The decrease in the ratio of new tips greater than 0.5 cm and longer at lower temperatures suggests that root elongation was suppressed more than t i p i n i t i a t i o n . Lopushinsky and Kaufmann (1984) planted two-year old, bare-root Douglas-f i r seedlings i n pla s t i c pots, at s o i l temperatures of 1.3 and 20.2 degrees C. Transpiration rate declined linearly with decreasing s o i l temperature, and at 1.3 degrees C was only 18.8% of the rate at 20.2 degrees C. Xylem pressure potential of seedlings exposed to a moderate evaporative demand averaged -15.4 bars, compared to -11.1 bars for seedlings in warm s o i l . Seedlings exposed to a high evaporative demand averaged -20.0 bars in cold s o i l , compared to -13.4 bars in warm s o i l . Stomatal conductance of seedlings in cold s o i l was 50% or less of seedlings in warm s o i l . Low s o i l temperature delayed bud burst, reduced shoot growth, and completely prevented root growth. Dobbs and McMinn (1977) grew white spruce germinants in growth chambers for 17 weeks at constant s o i l temperatures of 10, 15, 20, 25 and 30 degrees C, in favourable aerial conditions. At the conclusion of the experiment, heights, basal diameters of shoots, and ovendry shoot and root weights were recorded. Best growth in respect to a l l measured parameters was registered by seedlings grown in 20 degrees C s o i l ; next best treatments i n descending order were 25, 15, 30 and 10 degrees C. The differences between the 10 and 15 degrees C treatments were so great as to suggest a physiological threshold between these s o i l treatments. Bowen (1970) studied the effects of s o i l temperature on root growth and on phosphate uptake along Pinus radiata roots. Increasing s o i l temperature from 15 to 25 degrees C approximately doubled to t a l root length of 3-week seedlings; primary root length was increased but the main effect was due to a marked increase in the number and length of late r a l roots. Lateral root growth of the 3-week seedlings was almost completely suppressed in the s o i l at 11 degrees C, Heninger and White (1974) investigated the effect of s o i l temperature on shoot and root development of three conifers and two broadleaved species. Plants were raised from seed through two 8-week stages in environmental chambers with s o i l temperatures of 15, 19, 23, 27 and 31 degrees C. White spruce and tree-of-heaven had optimal shoot and root growth at 19 degrees C. Jack pine growth was maximum at 27 degrees C. Douglas-fir seedlings developed well between 15 and 27 degrees C. Paper birch grew well between 19 and 31 degrees C with best shoot development at 31 degrees C, whereas root development was favoured at 23 degrees C. The findings of these studies support those of Soderstrom (1981) who states that "for spruce, the optimum s o i l temperature i s about 20 degrees C, and for pines as high as 25 - 30 degrees C". Other studies suggest 5 to 10 degrees C as a minimum threshold temperature for root growth (Binder et a l . 1987, Macadam 1988). Low s o i l temperature not only affects root growth but reduces water uptake by reducing c e l l membrane permeability and increasing the viscosity of water (Kramer and Kozlowski 197 9). Running and Reid (1980) studied s o i l temperature influences on the root resistance of two-year old lodgepole pine seedlings. Short term measurements of leaf conductance, leaf water potential and t r i t i a t e d water movement were taken at root temperatures, from 22 degrees C down to 0 degrees C. Root resistance was calculated to be 67% of to t a l plant resistance at 7 degrees C and 93% at 0 degrees C. An abrupt change in root resistance below 6 degrees C suggests significant change with temperature in the membrane pathway in the root water uptake system and may be a result of phase transition of l i p i d s in these membranes. Grossnickle and Blake (1985) planted cold-stored jack pine and white spruce seedlings in a controlled environmental chamber providing an a i r temperature of 22 degrees C, s o i l temperatures of 22, 16 or 10 degrees C, and s o i l moisture near f i e l d capacity. After 21 days, root growth for white spruce was limited at a l l s o i l temperatures, whereas jack pine showed limited root growth at a s o i l temperature of 10 degrees C but extensive root growth at 22 degrees C. During the 21 days of observation after removal from cold storage, stomatal response patterns changed during the transition phase from darkness to f i r s t l i g h t . Jack pine seedlings showed increasing stomatal opening for seedlings in the 22 degrees C root temperature treatment, while a l l white spruce seedlings exhibited a greater stomatal closure during darkness. In both species, seedlings at lower s o i l temperatures experienced greater i n i t i a l water stress than seedlings at higher s o i l temperatures, the difference being associated with greater water-flow resistance through the soil-plant-atmosphere continuum (SPAC). In both species, xylem pressure potentials increased with time at a l l temperatures, a change attributable to a decline in water-flow resistance through the SPAC. This decline was possibly due to either a change in permeability of older suberized roots or, as in the case of jack pine at the higher s o i l temperature, a significantly greater development of new unsuberized white roots. Grossnickle (1988) planted bare-root 2+0 jack pine seedlings and 11/2+ 1 1/2 white spruce transplants in 8 cm diameter pots held at approximately 22 degrees C for 7 and 28 days. These, together with trees fresh from cold storage, were placed in aerated water maintained at 0, 6, 14, 15, or 22 degrees C. After 18 hours, water relations measurements were made. Seedlings were also planted in mineral s o i l on a s i t e - prepared area i n northeastern Ontario on four dates between May 6 and June 5, during which s o i l temperature at a depth of 15 cm increased from 0 to 18 degrees C. On each planting date, additional seedlings were placed with roots in aerated 18 water i n buckets set in the ground. After 28 days in the greenhouse, both species had produced many new unsuberized roots. Needle conductance of cold stored seedlings was measured one day after plants were transferred from cold storage to a warm greenhouse where they were placed with their roots in aerated water at a controlled temperature (1-day plants). There was l i t t l e diurnal variation, but in both species conductance decreased with root temperature. In both species xylem pressure potential also decreased with decreasing root temperature, both in plants in the greenhouse in aerated water and in field-planted trees the day after planting, with the latter having generally lower values. Needle conductance of jack pine seedlings grown in pots for 28 days before being placed in aerated water decreased with root temperature although the values were higher throughout the day than for 1-day seedlings. Xylem pressure potentials of the 28-day jack pine were similar, however, to those of 1-day seedlings. For 28-day white spruce, needle conductances were higher than those of the 1-day plants early in the day but declined by the afternoon to values as low as or lower than those of the 1-day plants. Xylem pressure potential, however, was higher than the 1-day plants throughout the day. Seedlings of both species grown in the greenhouse for 1 or 7 days showed an increase in water flow resistance in the soil-plant-atmosphere continuum (RSPAC) as root temperature decreased from 22 to 0 degrees C. The RSPAC of plants grown for 28 days was approximately half that of the 1-day plants. Compared with 1-day greenhouse plants in aerated water, trees planted in the f i e l d i n mineral s o i l had higher RSPAC values at temperatures from 6 to 14 degrees C, but sl i g h t l y lower values at 2 degrees C. Relative resistance of 1- and 7-day plants increased with decreasing temperature i n both species, although the rise i n resistance below 5 degrees C was much sharper for jack pine than in white spruce. In both species the increase in relative resis-tance was greater than the increase in the relative viscosity of water over the same temperature range. Relative plant water flow resistances of 28-day plants of both species increased with decrease in root temperature, although they were lower than in 1- and 7-day seedlings, and for white spruce were no greater than the increase in the relative viscosity of water. Although the decline in needle conductance was accompanied by a decline in xylem pressure potential, even at lower root temperatures, xylem water potential rarely f e l l below the reported turgor loss point of stock freshly removed from cold storage, thus indicating the operation of a mechanism that curtails water loss with decreasing root temperature before severe water stress, develops. The increase in plant resistance to water flow with decreasing s o i l temperature is attributed to the combined effects of the increased viscosity of water and reduced root permeability. However, 2 8-day spruce seedlings with many new, unsuberized roots showed markedly decreased plant water flow resistance particularly at low temperatures, indicating that trees may be more susceptible to water stress induced by low s o i l temperature when f i r s t planted than later on. This supports the results of post-planting studies of white spruce carried out by Binder et a l . (1987). Physiological evidence suggested that the condition traditionally called "growth check" in white spruce may actually be a resulting consequence of an inelastic physiological drought avoidance mechanism in this species. White spruce apparently maintains an early growth season daytime operational xylem pressure potential (xpp) of approximately -1.6 MPa. If replacement, by the roots, of water lost through transpiration cannot maintain this d e f i c i t stomates close up shutting photosynthesis down in under 20 minutes. Once stomates are closed they do not reopen that day. The amount of time stomates open the next day depends on the amount of water recharge during the dark period. If predawn xpp is below -1.0 MPa this time period may be very short. The osmotic adjustment to about -2.0 MPa therefore allows physiological function during summer drying and is most l i k e l y a natural consequence of frost hardiness induction. If this hypothesis is correct "growth check", because of i t s survival value, can never be and should never be cured. Its negative affect on growth may be greatly reduced by providing favourable microsite conditions through well-founded s i l v i c u l t u r a l practices. The most important of these include: 1) providing s o i l temperatures above 15 degrees C at planting; 2) reducing vapour pressure d e f i c i t ; and, 3) reducing background radiation levels about 30-35% yet insuring light intensity levels above 600 uE m"2 s"1. Grossnickle and Blake (1987) studied the water relations and morpho-logical development of bare-root jack pine and white spruce seedlings planted on a boreal cut-over site in northern Ontario. Comparison of morphological development between the two species showed jack pine seedlings had greater new root development and a lower new shoot/new root ratio, while white spruce seedlings had greater new shoot development. Seasonal water relation patterns showed white spruce seedlings to have a greater decrease in xylem pressure potential (xpp) per unit increase in transpirational flux density in comparison to jack pine seedlings. These results suggest that the greater resistance to water flow through the soil-plant-atmosphere continuum in white spruce seedlings compared to jack pine seedlings may be due to the relative lack of new root development in white spruce. Stomatal response of the seedlings showed that as absolute humidity d e f i c i t between needles and a i r (AHD) increased, needle conductance decreased in both species, but at very low AHD levels white spruce had. needle conductance approximately 35% higher than jack pine. For white spruce seedlings, needle conductance decreased as xpp became more negative in a predictable curvilinear manner, while that of jack pine seedlings responded to xpp with a threshold closure phenomenon at approximately -1.75 MPa. Tissue water potential components for jack pine and white spruce seedlings at the beginning and end of the growing season showed jack pine to reach turgor loss at 7 6% relative water content while white spruce reached turgor loss at 88% relative water content. White spruce seedlings showed osmotic adjustment over the growing season, with osmotic potentials at turgor loss of -1.27 MPa and -1.92 MPa at the beginning and end of the growing season, respectively. Jack pine did not show any osmotic adjustment over the growing season. The consequence of jack pine stomatal response to changes in xpp i s that the threshold phenomenon allows for normal diurnal variation in xpp but does not cause stomatal closure, while white spruce exhibited a negative feedback system which resulted i n immediate stomatal closure as xpp decreased. This suggests that the stomatal response of jack pine would allow growth to occur over a wider range of f i e l d conditions, while white spruce stomata are more restrictive over the range of f i e l d conditions they can tolerate. Microclimate data collected by Binder et a l . (1987) indicated that weather conditions severe enough to retard photosynthetic rate through reduced stomatal conductance might occur over as much as half the growing season. 22 1.1.4.2 Soi l Moisture Constant high water tables have also been shown to limit root growth. Lieffers and Rothwell (1986) studied the effects of depth of water table and substrate temperature on root and top growth of Picea mariana and Larix l a r i c i n a seedlings. Three-week old seedlings were planted in thermally insulated tanks, with one half receiving a cooling treatment and the other an ambient treatment (9 and 18 degrees C at 10 cm depth, respectively). Water table levels of the tanks were maintained at 4, 10 and 25 cm below the substrate surface. After 90 days, there were highly significant differences in seedling size among water table treatments, for both species. Mean root biomass for black spruce in the 25 cm versus the 4 cm tank was 0.027 and 0.006 g, respectively. Mean shoot biomass of black spruce seedlings was 0.180 and 0.034 g i n the 25 and 4 cm tanks, respectively, and for tamarack 0.666 and 0.083 g, respectively. For both species maximum rooting depth of seedlings and maximum root length were significantly longer in the 25 cm tank. Few roots penetrated below the water table in any of the tanks, and roots near the water table were usually blackened and some had necrotic ti p s . Root orientation was more horizontal in the 10 and 4 cm tanks. There were important interactions between temperature and water level treatments. With above ground size the ambient half of the 25 cm tank had larger seedlings than the cooled half; in contrast, the cooled half of the 4 cm tank had larger seedlings than the ambient half. The same was true for rooting depth, root length, and root:shoot ratio. These factors were depressed by cooling in the 25 cm tank but were increased by cooling in the 4 cm tank. Periodic flooding of variable duration has resulted in root mortality and plant moisture stress. Levan and Riha (1986) studied the response of root systems of four conifer species to flooding. Two- to four-year old nursery transplants of white pine, red pine, white spruce and black spruce were removed from cold storage, root pruned to 15 cm below the root-shoot junction, potted, and placed in a growth chamber at a temperature of 23 degrees C. Treatments were begun after bud break and needle elongation were complete and root systems had i n i t i a t e d new growth. A sub-sample of seedlings was subjected to a fixed water table 25 cm below the s o i l surface and root penetration measured for 30 days, u n t i l a l l had reached a maximum. Within each species, roots that had grown into the water table were compared with above water table roots to determine whether an obvious increase in internal pore space had occurred. A second sub-sample of seedlings was subjected to a similar water table flooding for periods of 1, 3, 5, and 7 days. Following drainage roots were observed for signs of recovery: either apical or lat e r a l , or no recovery. Transpiration was monitored for a l l treatments. Penetration into the water table by white pine, red pine, and black spruce was similar, with most roots confined to the surface 5 cm and the deepest roots at 8 to 10 cm. White spruce showed exceptionally poor growth into the flooded s o i l , with roots penetrating to only 2 cm in this 30-day period. There was no sign of pore space in either the cortex or the stele of any of the conifer roots that had grown into the water table. The conifer root growth that did occur may have been supported by oxygen diffusing through the intercellular spaces of the cortex. Water table penetration may have been compressed by the relatively high experimental s o i l temperature. In both red and white pine, many of the flooded root apices survived flooding and resumed growth after drainage, even in the 7-day flooding treatment. Combined apical and latera l recovery by the pine root systems averaged 85% over a l l treatments. When flooded for only 1 day, the response 24 of the spruces was like that of the pines. Both apical and l a t e r a l recovery occurred, with late r a l emergence relatively delayed. Flooding for longer than 1 day k i l l e d a l l flooded root tips of both white and black spruce. In the 3-, 5- and 7-day flooding treatments, post drainage root systems consisted entirely of replacement laterals that emerged between the 6th and 20th day after drainage. Recovery averaged 65% over a l l treatments. Transpiration response to flooding was similar for a l l species and a l l lengths of flooding treatments. Beginning with the f i r s t day of flooding, transpiration tended to be depressed below control levels; by the 5th to 7th day of flooding, transpiration rates had declined to 50-60% of controls, but recovered to control rates quickly after drainage. The transpiration recovery was equally fast in the spruces and the pines, even though the spruces had no growing tips present u n t i l after transpiration had recovered. Thus, either growing tips are not necessary for the recovery in transpiration or the few growing roots that were present in the unflooded s o i l were adequate for the resumption of normal water uptake. Laboratory data from Binder et a l . (1987) indicated that white spruce requires approximately 6 new roots greater than 1 cm to maintain proper water balance, flush and remain healthy"under well watered, growth room conditions. Grossnickle (1987) studied the influence of flooding and s o i l tempera-ture on the water relations and morphological development of cold-stored black spruce and white spruce seedlings. Seedlings were planted in a controlled environment chamber with an air temperature of 20 degrees C, and s o i l temperatures of 10 or 20 degrees C. Root development was sampled for: extended nonflooded treatment (42 days); 14 day nonflooded - 14 day flooded -14 day nonflooded treatment (nfld-fld-nfId); and, 28 day flooded treatments. On the f i r s t day after planting and at 3 to 4 day intervals u n t i l the 28th 25 day, measurements of xylem pressure potential, stomatal conductance, and transpirational flux density were made. Black spruce seedling morphological development was influenced by flooding and s o i l temperature treatments. At both s o i l temperatures, nonflooded seedlings had greater shoot development and root development compared with other treatments. Flooded seedlings showed the least shoot growth and produced no new roots over the 28 day study period. Seedlings flooded for 14 days and then released from flooding were just beginning to show signs of root development after a further 14 days. Released seedlings had white root tips while flooded seedlings had no white root t i p s . Nonflooded seedlings in the 20 degrees C s o i l treatment showed greater shoot and root development compared with nonflooded seedlings at the 10 degrees C s o i l treatment. Shoot development of white spruce seedlings was not influenced by flooding or s o i l temperature treatments. At both s o i l temperatures, seedlings in the flooded and flooded/released treatments showed no root development. Nonflooded seedlings in both s o i l temperature treatments showed root development, but greater root development occurred in the 20 degrees C s o i l temperature treatment. Black spruce seedlings, in both s o i l temperature treatments, had continued root development during flooding i f allowed 14 days out of cold storage before given a 14 day flooding treatment. However, root development was reduced in comparison with seedlings in the nonflooded treatment. In both the control and nfld-fld-nfId "treatments, root development was greater in the 20 degrees C s o i l temperature treatment. Seedlings flooded for 28 days showed very l i t t l e or no root development. White spruce seedling root development was suppressed for seedlings in the nfld-fld-nfId treatment compared with control seedlings. The flooding treatment for n f l d - f l d - n f l d seedlings resulted in no new root development during day 28 to day 42 in the nonflooded s o i l treatment. Root development was nonexistent at day 28 in seedlings that were flooded for 28 days right after removal from cold storage. Stomatal conductance of seedlings just removed from cold storage was reduced in both flooded and nonflooded treatments. However, the longer the seedlings were exposed to the s o i l treatment after removal from cold storage, the greater the difference in diurnal stomatal conductance. Nonflooded seedlings of both species showed an increase in diurnal stomatal conductance patterns u n t i l 14 days out of cold storage. Diurnal stomatal conductance of both flooded black spruce and white spruce seedlings was greatly reduced compared with nonflooded seedlings. After white spruce seedlings were released from flooding there was a gradual increase in the diurnal stomatal conductance to levels greater than nonflooded seedlings. This response was possibly due to stomatal damage, which reduced the seedling's a b i l i t y to control water loss during daytime hours. Diurnal xylem pressure potential (xpp) for flooded and nonflooded seedlings showed flooded seedlings for both species to have more negative diurnal xpp just after removal from cold storage. Flooded white spruce seedlings continued to have more negative xpp over the length of the study. Flooded black spruce seedlings did not show this daytime xpp pattern. In both species, predawn xpp measurements indicated that flooded seedlings had more negative xpp than nonflooded seedlings at the beginning of each day. Thus, flooded seedlings did not have the a b i l i t y to take up a comparable amount of s o i l moisture as nonflooded seedlings during the dark period, 27 presumably because of reduced root system hydraulic conductivity. Seedlings of both species at a l l s o i l temperature - flooded treatment combinations showed a high resistance to water flow through the soil-plant-atmosphere continuum (RSPAC) 1 day out of cold storage. Changes in water flow characteristics occurred for nonflooded seedlings of both species at both s o i l temperatures over the course of this experiment. By day 21 white spruce seedlings showed a large RSPAC difference between s o i l temperature treatments, whereas black spruce did not show a large RSPAC difference between seedlings at 10 and 20 degrees C s o i l temperature. This indicates that white spruce seedlings are more sensitive to s o i l temperature than black spruce seedlings. Continued flooding resulted in higher RSPAC at 21 days compared to nonflooded seedlings of both species, thus indicating that flooded seedling root systems were less e f f i c i e n t at taking up water to meet the seedling transpirational demand. 1.1.5 Summary Mechanical site preparation treatments have been shown to positively affect seedling performance. However, differences in seedling response have been found between and among species, site, and treatment combinations, indicating the need for site specific prescriptions. S o i l temperature and s o i l moisture have been identified as the edaphic factors most important in the establishment phase. Mechanical site preparation treatments have been shown to alter s o i l temperature regimes by affecting changes in s o i l thermal admittance and d i f f u s i v i t y . Treatments which expose mineral s o i l make the planting microsite more responsive to changes in diurnal and seasonal climate. 28 The importance of stimulating root growth was stressed by many authors. Both low s o i l temperature and high s o i l moisture were shown to negatively affect seedling root growth. Optimal root zone s o i l temperature was stated as approximately 20 degrees C for spruces and 25 to 30 degrees C for pines. A low threshold temperature of approximately 5 to 10 degrees C was shown to impede root growth and affect seedling moisture status by increasing root resistance to water flow. White spruce showed the least penetration, of a fixed water table, of any of the conifer species studied by Levan and Riha (1986), and was also the most intolerant of any length of periodic flooding. The importance of rapid root i n i t i a t i o n to maintain seedling water balance was stressed. Growth check in white spruce was hypothesised as being a physiological response to low xylem pressure potential, and can only be overcome by maintaining good seedling water balance. The increased suscep-t i b i l i t y of seedlings fresh out of cold storage was shown and emphasized the need for rapid achievement of optimum root zone temperatures. 29 1.2 Objectives The objectives of this thesis are: 1) to provide a summary of f i r s t year results of the root egress study; and, 2) to correlate root egress data with other data collected under the FRDA 1.10 study. Based on the literature review i t was hypothesised that: 1) root egress would be a good, early indicator of site preparation treatment s u i t a b i l i t y and success; 2) numbers of new roots greater than 1 cm i n length would be greatest on treatments with the warmest root zone temperatures; 3) root i n i t i a t i o n would primarily occur from the end of the root plug, at least i n i t i a l l y , but continued root development would d i f f e r between the two species; 4) l i t t l e root growth would occur u n t i l root zone temperatures warmed to levels above 10 degrees C; 5) there would be l i t t l e difference in the f i r s t year morphological response to the different treatments; 6) there would be l i t t l e difference in the f i r s t year f o l i a r analysis data, however, N concentration would be monitored for any dilution effect caused by rapid growth and P concentration monitored for deficiency due to increased available N in any treatment. 30 2 Materials and Methods 2.1. Site Selection Site selection was assumed by the B r i t i s h Columbia Ministry of Forests (MOF) and Forestry Canada. Four locations were chosen for site preparation during the summer of 1986, and were considered representative of major backlog types where stand establishment has been hampered by cold moist soi l s and vegetative competition (Hedin 1987) . Ecosystem association and s o i l type were also identified as part of site selection (Bedford 1986). The study site locations were near Fort St. John, Dawson Creek, Mackenzie, and Vanderhoof, and are shown in Figure 1. 2.2 Site Description The ecological c l a s s i f i c a t i o n and s o i l characteristics of the sites are summarized in Table 1. A detailed description of s o i l texture and humus depth/form is presented in Appendix A. 2.2.1 Iron Creek The Iron Creek site was located approximately 120 km northwest of Fort St. John (56°N 122°W) . The site i s in the Halfway River Moist Cold Southern Boreal White and Black Spruce variant (BWBSd2). The s o i l i s fine-textured, s i l t y clay loam and clay loam. The area was selectively logged in 1966; clearcut in 1974; and windrow sca r i f i e d in winter 1985. Study plots were located between the windrows and mechanically site prepared in summer 1986. 31 Figure 1. Location of study sites (from Hedin 1987) 32 Table 1. Characteristics of treatment sites as summarized from control plot descriptions, at each location, by MOFL (from Hedin 1987). Location Ecological classification Humus Humus depth Soil texture Soil moisture Coarse form" (cm) fragments Fort St. John Moist Cold Southern Boreal moder (mor) 11-14(7) White and Black Spruce BWBSd2 variant 06 Association - White Spruce -Horsetail (05 Assocation - Highbush-cranberry - Tall Bluebells) Dawson Creek Moist Cool SouthernBoreal moder 14-18(8) White and Black Spruce B W B S d variant 05 Association - Highbush-cranberry - Oak Fern (06 Association - Highbush-oranberry - Tall Bluebells) (07 Association - Spruce -Horsetail) Mackenzie Moist Cool Central Sub-Boreal mor (moder) 1-2(10,16) Spruce SBSJ2 variant 01 Association - Black Gooseberry - Oak Fern 03 Association - Black Huckleberry - Bunchberry (04 Association - Devil's Club - Oak Fern) Vanderhoof Moist Cold Central Sub-Boreal mor (moder) 2-8 Spruce SBSi subzone 01 Association - Prickly Rose -Colt's-foot silty clay loam subhygric (clay loam) (hygric, mesic) <5% sandy loam, subhygric clay loam (hygric) sandy silt, silty sand (silt loam) silt loam <2% mesic (submesic) subhygric) <2% 10% (20%, 30%) a Bracketed descriptions are minor components of the site. 33 2.2.2 Stewart Lake The Stewart Lake site was located approximately 50 km west of Dawson Creek (56°N 121"W) . The site i s in the Dawson Creek Moist Cool Southern Boreal White and Black Spruce variant (BWBScl). Soils are somewhat coarser textured than in Iron Creek, with sandy and clay loams. The area had been selectively logged several times in the past 30 years and was burned in the mid-1960's and in 1971. The aspen on the area had been sheared and windrowed during April 1986. Study plots were located between the windrows and mechanically site prepared in summer 1986. 2.2.3 Mackenzie The Mackenzie site was located approximately 5 km east of Mackenzie (55°N 123°W) . The area is variable, within the Fraser Basin Moist Cool Central Sub-Boreal Spruce variant (SBSJ2), but composed of three associations within that. Soils ranged from sandy s i l t to s i l t y loam with humus depth and rooting depth variable. The area had been logged in winter 1977 and chain-dragged in 1978. The brush, grass, and aspen on this site were more typical of a post-logging situation than the brush-bladed Iron Creek and Stewart Lake sites. Study plots were located and mechanically site prepared in sum-mer/fall 1986. 2.2.4 Kluskus Road The Kluskus Road site was located approximately 75 km southwest of Vanderhoof, off the Kluskus Forest Access Road (54°N 125°W) . The site i s within the Moist Cold Central Sub- Boreal Spruce subzone (SBSi). The soi l s are very compact, with 5-30% coarse fragments. Humus depth is 2-8 cm, and rooting depth ranged from 7 to 15 cm. This shallow rooting depth was l i k e l y a result of the compact features of the s o i l (Hedin 1987). The area had been summer and winter logged in 1977 with a full - t r e e feller-buncher/grapple-skidder system. Study plots were located and mechanically site prepared in summer 1986. 2.3 Experimental Layout The experimental layout followed that of FRDA Project 1.10. Each site had 30 x 40 m study plots established in a randomized complete block design; each with 5 blocks, each treatment represented once per block. FRDA 1.10 plots followed the 'mini-stand' approach outlined i n McMinn (1984) in which seedlings were planted such that one treatment plot, consisting of 8 rows of 10 seedlings, would eventually form a stand of trees a l l exposed to the same treatment. Seedlings for the root egress study were planted, with care not to disturb the FRDA 1.10 seedlings, on or directly adjacent to these plots in surplus microsites judged to be representative of the study treatments. Figures 2 - 5 show plot layout and assignment of treatments for each s i t e . Note, not a l l treatments are represented on a l l sites, and not a l l treatments shown are incorporated in this study. 2.4 Site Preparation Treatments The site preparation treatments used in this study reflect current and future systems used in backlog rehabilitation. For more information on specific equipment see MacKinnon et a l . (1987) and Coates and Haeussler (1984). This study was meant to provide an i n i t i a l biological assessment of these systems, and the microsites each system produces, under "operational" f i e l d conditions. Microsites selected for this study reflect the actual, as opposed to the theoretical, microsites each system or implement produces. Each microsite and planting position i s represented in Figure 6. . i-u. e-i, »-«, i-t . 1-10, C-l, »-». t-10 o. t-1, C-1. »-/. I-| , »-4. e-*, (-] . i-j. e-j, B-i, 1-1  A-l, B-«. t-1 MI $ ». n i-u t.i. at* H»r imiiuii I >|J I.L.1MS M G . / R . W . I R O N C R E E K 60.OG1CAI.PI (T I D A T E I >T3 i6-Qft-37J Figure 2. Plot layout and assignment of treatments, Iron Creek site. 35 ft-10 A-7 A-6 A-3 A-2 A-9 A-8 A-5 A-4 A-l B - I D-2 V. 0-1 ) 1 X 4 /// 7/ E-7 E-10 ...... / »-* l-I CH D-« t-A »-J e-i »-» i-io -1 1-10 »-) (-> E-a E-» / • D R BYJ M . G . . R . W . S T E W A R T L A K E D A T E B I O L O G I C A L P L O T S 86-06-27 Figure 3. Plot layout and assignment of treatments, Stewart Lake s i t e . 36 Figure 4. Plot layout and assignment of treatments, Mackenzie s i t e . 1. HI*l*(tT M -J, C-l. D-*. 1-1 <U(*ra(a S<«. -J. 1-1. C-  D-l. I-# -7, 1-1. C-l, »-). C-l **. C-l. It-*, t-l -i. i-*. c - i . o-*, t-« -I. C-*. D-J. t-« T(*ala~>f « J. 1 J-IJ 1, . t m -tl t.L. ISH 3R BY M.G..RW. KLUSKUS BIOlOnirAI PI OTS DM6 86-07-21 Figure 5. Plot layout and assignment of treatment, Kluskus Road s i t e . 37 d u f f l a y e r m i n e r a l s o i l > «!*«''* ,*> m i x e d Figure 6. Diagram of (a) control, (b) patch, (c) Donaren trench, (d) Bracke mound, (e) Sinkkila mound, (f) Ministry mound, (g) breaking plow, and, (h) V-blade treatment microsites, and planting positions studied. 38 Hedin (1987) conducted f i e l d assessments of the inverted humus mounds produced by the Ministry Mounder, SinkkilS HMF Scarifier/Mounder, and Bracke Mounder, as part of the FRDA 1.10 Project. Mound configuration (mineral s o i l capping, height, length, and width) was measured in September 1986. 2.4.1 The Ministry Mounder The Ministry Mounder was developed by the Silviculture and Engineering Branches of MOF over a 6 year period. Operational t r i a l s of an early prototype are summarized in Parolin et a l . (1981). The prototype used in this study was mounted on a Cat D7E crawler, equipped with floatation tracks and a V-blade. Digging buckets are mounted on the ripper parallelogram of the machine on the rear of the crawler. Hydraulic pressure i s used to drive the buckets into the ground while the machine i s moving forward. The buckets are raised and then flipped to produce an overturned mineral mound over inverted organic material. The hydraulic pressure can be adjusted to suit s o i l conditions and the desired mound configuration, and digging cycle and spacing are adjusted using onboard computer controls. The Ministry Mounder was the only mounder used on the Kluskus Road site as i t was the only implement judged to be able to form successful mounds.in these compact and stony soils (Hedin 1987). 2.4.2 The Sinkkila" HMF Scarifier/Mounder The Sinkkila HMF Scarifier/Mounder is a modified version of e a r l i e r machines used in Finland for patch scarification. The machine was mounted on the rear of a John Deere 740 skidder and consists of two s c a r i f i e r units, 2 m apart, each with four pairs of ripper tines. As the machine is pulled forward a hydraulic brake is applied to the ripper wheel and the tines are drawn through the organic material and into the mineral s o i l . When the brake i s released the ripper rotates, and the organic/mineral s o i l accumulation overturns forming a mound. Depending upon the angle of the ripper and the hydraulic braking applied to i t , mounds, scalps, or continuous shallow furrows can be produced. The unit was used at the Kluskus Road site to produce the patch treat-ment. The scarification action i s similar to that described above but the tines are held at a less aggressive angle and only penetrate and overturn the organic/duff layer. 2.4.3 The Bracke Mounder/Patch Scarifier The Bracke Mounder is an adaptation of the Bracke cultivator used in Scandinavia and Canada for patch scarifying. It consists of two units housed in box frames mounted on a drawbar frame. Each unit consists of a rubber t i r e and tined mattock wheel linked by a chain mechanism through a gearbox. As the unit i s pulled forward the mattock wheel rotates, at a slower speed, and the mattock tines move through the s o i l to produce a scalp and inverted accumulation. A mineral s o i l cap i s produced by a tined shovel mounted behind the mattock wheel which digs into the scalp and deposits additional mineral s o i l on the inverted accumulation as the shovel l i f t s . The shovel i s hydraulically powered by an auxiliary engine mounted on the frame. The Bracke unit was mounted behind a Clark 6 6 8 skidder for this t r i a l . The Bracke unit was used on the Iron Creek, Stewart Lake, and Mackenzie sites for both mounding and patch treatments. To create patches the cycle i s as above except the tined shovel is not activated. 40 2.4.4 The Breaking Plow The Breaking Plow used for this study consisted of three long plow shares mounted on an angled frame. The unit was mounted to the rear of a crawler tractor. The unit i s pulled forward with the plows cutting through the mineral s o i l below the duff layer. The continuous mineral soil/organic clod i s inverted as part of the plow action to produce a continuous inverted mineral over humus ridge. The two inside ridges are placed on the mineral s o i l exposed by the adjacent plow, with the outside ridge placed directly on the undisturbed humus layer. On a continuously plowed site the outside ridge would be placed on the exposed mineral s o i l of the adjacent pass. 2.4.5 The V-Blade The V-Blade used for this study (Beale's V-blade) was mounted on the front of a D7 crawler tractor and consisted of a large shearing blade formed into a "V" shape. As the unit moves forward the forward shearing edge cuts along the organic, rootmat/mineral s o i l interface and removes any debris, slash, or vegetative competition, thus forming a wide, screefed corridor of exposed mineral s o i l . 2.4.6 The Donaren 180 The Donaren 180 is a powered disc trencher designed to produce continu-ous furrows of exposed mineral s o i l . The unit was mounted on the rear of a large skidder, and consists of two tined discs mounted on adjustable arms held at an angle to machine travel. The arms are supplied with hydraulic down pressure and the discs are hydraulically powered to rotate in the same direction as that of machine travel. As the unit i s pulled forward the discs cut through the organic layer to the mineral s o i l , forming a furrow. The 41 organic material and mineral s o i l removed are placed to one side of the furrow forming a loose berm of material. Penetration of the discs i s controlled by adjusting hydraulic down pressure to the arms. Unfortunately, preparation of the Mackenzie site was delayed t i l l late in the f a l l , and penetration was limited by the frozen s o i l . Penetration was also limited on the Kluskus Road site by the very hard s o i l and the large number of rocks. 2.4.7 Untreated Control The control treatment for this study was a microsite i n which the seedlings were planted directly into undisturbed duff-covered mineral s o i l . Some light boot-screefing was done by the planters. 2.5 Planting Stock A l l seedlings planted were grown in styroblocks, fall/winter 1986 l i f t e d , and cold stored t i l l time of planting. Table 2 summarizes seedling stock information. Several days prior to planting, bundles were removed from their boxes and unwrapped. Seedlings were individually inspected. Twenty to twenty-five percent were culled for any of the following reasons: seedlings abnormally large or small, root plug damaged, seedling chlorotic, heavy mold, multiple seedling per plug, multiple leader, and leader broken or damaged. Seedlings for the Stewart Lake site were heavily infested by grey mold. Bundles were re-wrapped and placed back in their boxes. Inspections were carried out inside the reefers and exposure of the root plugs kept to a minimum. Upon commencement of planting the boxes of seedlings were cached on or near the study site, or removed from the reefer on a daily basis where convenient. A sub- sample of approximately 50 seedlings per seedlot was taken at random during the plant and sent to the MOF Red Rock Research Station for morphological measurement and root growth capacity (RGC) testing, following Simpson (1985) and Hooge (1987). Unfortunately, the sample from Mackenzie was misplaced and not tested. Results are summarized in Table 3. Table 2. Summary of seedling stock information S i t e S p e c i e s S t o c k T y p e S e e d l o t L i f t i n g D a t e P e r c e n t I r o n G r e e k W h i t e s p r u c e 1+0 P S B 313 2665 n / a 24 S t e w a r t L a k e W h i t e s p r u c e 2+0 P S B 313 8782 n / s 20 M a c k e n z i e W h i t e s p r u c e 1+0 P S B 313 29144 5 Dec 86 22 K l u s k u s R o a d L o d g e p o l e p i n e 1+0 P S B 211 8574 17 N o v 86 24 Table 3. Summary of morphological measurements and RGC testing. S i t e S e e d l o t RGC C l a s s S h o o t L e n g t h (mm) R o o t C o l l a r D i a m e t e r (mm) S h o o t M a s s ( « ) R o o t M a s s ( B ) I r o n C r e e k 2665 2.69 175 2.7 1.5 0.8 S t e w a r t L a k e 8782 1.44 212 4.1 2.9 1.5 M a c k e n z i e 29144 n / a n / a n / a n / a n / a K l u s k u s R o a d 8574 4.56 171 2.2 0.7 0.4 2.6 Planting A l l planting was carried out in Table 4 l i s t s planting dates for the spring 1987 by two contract planters, four sites. Seedlings were planted 43 Table 4. Planting dates by si t e . Site Planting Date Kluskus Road May 12 - 18, I987 May 20 - 26, I987 Stewart Lake Mackenzie Iron Greek May 28 - June 2, 1987 June 4 - 1 0 , 1987 using modified planting shovels and the " s l i t method" (Robertson and Young 1988). Planting spots were flagged prior to planting in a l l but the control, Donaren 180, Sinkkila mound, and breaking plow treatments. Final microsite selection was, however, l e f t up to the planters' discretion. The planters were instructed prior to planting each treatment what the desired, represen-tative microsite was. This was done in consultation with R. G. McMinn. For the untreated control treatment, seedlings were planted directly into the undisturbed, duff-covered mineral s o i l . For the patch treatment, seedlings were planted on the shoulder of the patch near the hinge of inverted organic/mineral s o i l . For the Donaren 180 treatment, seedlings were planted on the shoulder of the furrow adjacent to the berm of mixed organic/mineral s o i l . For the V-blade treatment, seedlings were planted in the exposed mineral s o i l of the screefed corridors approximately 25 cm from the berm of cleared, mixed debris, duff and mineral s o i l . For the breaking plow treatment seedlings were planted only on the ridges of inverted mineral soil/organic overlaying mineral s o i l . For a l l mound treatments seedlings were planted directly into the mineral mound over inverted humus. Planting position i s shown i n Figure 6. For the breaking plow and mound treatments, seedlings were planted such that part of the root plug extended through the inverted humus layer, even though this resulted in the root collar being buried up to 12 cm on deep mounds. Experience in Scandinavia suggests that this would not reduce survival (McMinn, pers. comm.). Studies have shown that the duff layer causes capillary discontinuity, which interrupts the upward movement of s o i l moisture, trapping i t below the discontinuity (Hunt 1987) . Seedlings planted J- rooted within the mineral s o i l cap do not reach the continuous supply of moisture beneath the duff. Deprived of s o i l moisture during drought periods, such seedlings may die or become stunted by drought (McMinn 1988). While this alters seedling shoot:root ratio in relation to other treatments studied, i t was f e l t that this provided the only chance for seedling survival on these microsites. Development and operational testing of container seedlings with a longer root plug i s ongoing. Depending upon the level of destructive sampling anticipated, either 30 or 50 seedlings were planted on each plot. Thus, 150 or 250 seedlings per treatment per site were planted. 2.7 Biological Assessment Sample seedlings were carefully excavated at approximately 45, 70 and 95 days after planting. Due to the lo g i s t i c s of the study only selected treatments were sampled for a l l three periods. The remaining treatments were sampled for the 95 day assessment only. Table 5 l i s t s the treatments studied and sampling intensity at each location. For each assessment date 10 seedlings i n each of 5 replications per treatment per site were sampled. Seedlings were placed i n pl a s t i c bags and taken to the Red Rock Research Station for immediate examination. Seedlings for the 95 day assessment were refrigerated and cold stored, in plastic bags at Red Rock u n t i l they could be transported to UBC for examination. Table 5. Treatments studied and sampling intensity at each location. S i t e Treatments Studied I r o n Greek Stewart Lake Mackenzie Kluskus Road Deep mound, M i n i s t r y mounder Shallow mound, Bracke mounder Patch, Bracke untreated c o n t r o l S i n k k i l a mound Breaking plow, i n v e r t Deep mound, M i n i s t r y mounder Shallow mound, Bracke mounder Breaking plow, i n v e r t Patch, Brake untreated c o n t r o l Donaren 180, shoulder S i n k k i l a mound Deep mound, M i n i s t r y mounder Shallow mound, Bracke mounder Patch, Bracke untreated c o n t r o l Donaren 180, shoulder S i n k k i l a mound Deep mound, M i n i s t r y mounder** Patch, S i n k k i l a untreated c o n t r o l Donaren 180, shoulder V-plow, screefed Sampling I n t e n s i t y -1^ 45, 70, 95 day - j ^ , 95 day only -I ^ 45, 70, 95 day 95 day only -1 ^ 45, 70, 95 day } Y 95 day only 45, 70, 95 day 95 day only *•* I n i t i a l l y t h i s treatment was separated i n t o deep and shallow mound treatments, however, a f t e r the 45 day assessment they were combined due to heavy m o r t a l i t y on t h i s s i t e . The roots of sampled seedlings were examined for egress of new roots from the root mass developed during the growth of seedlings in styroblocks. The root systems were carefully washed and the numbers of a l l unsuberized, white root tips t a l l i e d for the 45 and 70 day assessments. New roots which had grown from the i n i t i a l root mass but were already suberized were not included in the t a l l y . I n i t i a l l y only the number of white root tips was t a l l i e d , regardless of length or location. However, this provided only limited information. The 45-day assessment for the Kluskus Road site was the only assessment done this way. For the remaining assessments the t a l l y was . broken into four groups based on whether the new root was growing from the side or bottom of the plug (Figure 7), or was greater or less than 1 cm in length. Root egress for the 95 day assessment was measured for root area index using a Delta-T area meter (Figure 8). This device u t i l i z e s a video system to automatically quantify a projected, two-dimensional representation of the seedling's root system. The washed root system is cut, separated, and placed in a glass-bottomed root tray in a root box, over a light source. Care is taken to minimize overlap of the roots. A video camera is focused on the root system and projects this onto a standard video monitor. One scan of the video camera consists of approximately 250 individual scan lines, and i s completed in 1/60 second. The area meter consists of a comparator and a counter, and is set to measure the fraction of each scan line that has a brightness above or below a user determined threshold. The device i s then calibrated using an object of known area. In this case, a small piece of paper of known dimension was shredded and floated in shallow water in the root tray to simulate the root samples and allow for overlap. This method 47 SIDE END Figure 7. Diagram showing how the t a l l y of root egress was broken i n t o groups based on whether the new root was growing from the side or bottom of the root plug. VIOEO CAlMERA ROOT BOX ROOT TRAY light MONITOR U D Of OTT5 o o 0 A R E A ME*TFF Figure 8. Schematic diagram of root box, video system, and area meter used to measure root area index f o r the 95 day assessment of root egress (from Delta T Operator's Manual). 48 proved effective. Thus root area index values are a measure of the two-dimensional projected root system surface area in cm2 and can easily be converted to tot a l root surface area by multiplying by Pi. The t o t a l seedling height, root collar diameter and 1987 leader growth were measured for a l l 95 day seedlings. A sub-sample of two seedlings per plot was taken for measurement of root and shoot dry weight, shoot:root ratio, nitrogen and phosphorus content of 1987 seedling foliage, and dry weight of 100 needles of 1987 foliage. A l l samples were k i l n dried for 48 hours at 70 degrees C. Needles from the top 5 cm of the apical leaders of the two seedlings were bulked and used for the nutrient determinations. Mr. M. Tse, Faculty of Forestry, UBC, carried out the f o l i a r chemical analysis. 2.8 Analysis Analysis of variance, followed by Duncan's mean separation test where warranted, was performed on the biological assessment data using the SAS s t a t i s t i c a l package (SAS Institute Inc. 1985). 2.9 Environmental Monitoring Study (FRDA 1.25) An environmental monitoring study was undertaken as a subproject of FRDA 1.10 by the MOF, Prince George Region. Layout, monitoring setup and measurement i s outlined in McLeod and Osberg (1986). Root zone temperature and site climatic conditions were monitored for a l l three spruce sites. 2.10 Vegetation Ingrowth Assessment (FRDA 1.10) Vegetation assessments of ingrowth following site preparation and the development of vegetation on untreated plots was measured, in the second and thir d weeks of August 1987, by MOF personnel as part of the FRDA 1.10 project (McMinn and Bedford 1988). Ten seedling-centred plots were sampled in each of the 5 replicates of the representative treatments being assessed, making a to t a l of 50 sample plots, 2000 cm2 in area, per treatment. Tree seedlings in the centre of each plot were 25 cm from the circumference of the plot. Sample plot size was chosen to reflect the presence of competing vegetation within close proximity of tree seedlings. Additionally, tests have shown that plots of this size can be assessed with greater repeatability than larger plots (McMinn and Bedford 1988). The following estimates and measurements were made for each plot: 1) t o t a l percent cover of non-crop vegetation greater than 20 cm in height (i.e. t a l l e r than the seedling and therefore l i k e l y to compete with i t for l i g h t ) ; 2) names and cover of up to 3 species greater than 20 cm in height; 3) t o t a l percent cover of non-crop vegetation less than 20 cm i n height; 4) average height of non-crop vegetation; and, 5) distance of nearest vegetation from the tree seedling. A simple competition index was calculated as the percent cover of vegetation multiplied by the average height of vegetation divided by the distance of the nearest vegetation to the seedling (McMinn and Bedford 1988). 2.11 Survival and Frost Damage Survival and number of seedlings damaged by frost were t a l l i e d by MOF personnel in late August as part of the FRDA 1.10 Project. A l l FRDA 1.10 seedlings were examined. 50 3 Results 3.1 F i e l d Assessment of Mound Configuration (Hedin 1987) Table 6 summarizes the performance of the three mounding implements. A more detailed summary i s presented in Appendix B. Overall, the Ministry Mounder had the greatest success in producing inverted humus mounds on a l l four locations. It had the highest percentage of acceptable mounds of the three machines (79 - 95%), and mineral s o i l capping was consistently greater than 10 cm. The Sinkkila Mounder was inconsistent in i t s results. It performed well at Stewart Lake (80% acceptable mounds), but poorly at Mackenzie (44% acceptable mounds). The unsatisfactory performance at Mackenzie was due in part to mechanical malfunction. The Bracke Mounder was consistent in i t s overall performance on a l l three locations, with 70 - 80% acceptable mounds. However, the a b i l i t y of the machine to prepare mounds greater than 10 cm mineral s o i l capping was definitely dependent on, and limited by, the si t e . 3.2 Environmental Monitoring The period of study began approximately 1 week into August and termi-nated at the end of October. On a l l three sites solar radiation varied between 5 to 23 MJ/m2/day i n i t i a l l y but generally tended to decrease to levels between 5 to 10 MJ/m2/day into October. Daytime, maximum ai r temperature on a l l sites varied between 10 to 25 degrees C throughout the study period. Nighttime minimum air temperatures f i r s t dropped below freezing at the Iron Creek and Stewart Lake sites on September 12 and October 5 respectively. The Mackenzie site 51 Table 6. Summary of the performance of the three mounding implements (from Hedin 1987). Fort St. John % Acceptable mounds Dawson Creek Mackenzie Vanderhoof Sinkkila Mineral capping >10 cm Other acceptable mounds 21.5 60.5 52.5 27.0 3.8 40.5 N/A N/A Total acceptable mounds 82.0 79.5 44.3 N/A Ministry mounder Mineral capping >10 cm Other acceptable mounds 62.0 17.0 89.3 5.6 78.5 14.5 64.5 27.0 Total acceptable mounds 79.0 94.9 93.0 91.5 Bracke mounder Mineral capping >10 cm Other acceptable mounds 6.4 65.0 41.0 38.5 18.2 52.2 N/A N/A Total acceptable mounds 71.4 79.5 70.4 N/A was located in a frost pocket and nighttime temperatures frequently dropped below freezing throughout the monitoring period. 3.2.1 Root Zone Temperatures On the Iron Creek site, s o i l temperature at a depth of 10 cm reached the highest temperatures in the Ministry Mounder microsites. This treatment showed the greatest diurnal fluctuation of a l l treatments, with diurnal ranges up to 15 degrees C. It also showed the most response to changes in ai r temperature, precipitation and solar radiation. These two characteristics are i l l u s t r a t e d in Figure 9. The gradual decline in incoming solar radiation over the monitoring period i s accompanied 52 Figure 9. Plots of (a) solar radiation, (b) precipitation, (c) a i r temperature, and (d) root zone temperature in a mound microsite, monitored on the Iron Creek site (courtesy FRDA 1.25). 53 by a matching decline in average mound root-zone temperatures. A period of relatively high incoming solar radiation, a i r temperatures, and no precipi-tation between Julian days 246 and 255 results in matching high microsite temperatures. A decline in solar radiation on Julian day 251 i s matched by decreased microsite temperature. The combined effect of a large precipita-tion event and decreased solar radiation on Julian day 257 rapidly lowers a i r and microsite temperatures. Generally this treatment had many periods of daily maxima greater than 15 degrees C well into September and some peaks greater than 20 degrees C. Its minima were lower than a l l the other treatments and dropped below freezing f i r s t . S o i l temperature at a depth of 10 cm in the Bracke Mounder microsite followed a similar pattern to that of the Ministry Mounder microsite, however, i t had s l i g h t l y less diurnal variation and never achieved tempera-tures i n excess of 20 degrees C. It had periods of daily maxima greater than 10 degrees C well into September and some peaks greater than 15 degrees C. Soil temperature at a depth of 10 cm for the patch and control treatments was quite similar. Both showed only 2-3 degrees C of diurnal variation and a declining trend over the monitoring period from approximately 12 degrees C i n i t i a l l y to 5 degrees C. Soil temperatures at the humus/mineral interface for the control, Ministry and Bracke Mounder treatments followed the same trend with a diurnal variation of about only 1 degree C. At the Stewart Lake site the thermal regimes of the different microsites each followed the same general pattern as their counterparts in Iron Creek, however, the differences between the Ministry and Bracke Mounder microsites were somewhat less. Soil temperatures greater than 15 degrees C were seldom achieved for any significant period of time in either treatment. The patch 54 and control treatments again had similar trends; however, the patch treatment showed a diurnal variation of about 2 degrees C whereas there was l i t t l e diurnal variation for the control treatment. The control treatment also had the highest temperature at the end of the study period, at 5-6 degrees C, whereas the patch treatment had dropped to about 4 degrees C. At the Mackenzie site, the s o i l thermal regimes were again typical for the various microsites, however, the Bracke Mounder showed higher maxima and greater diurnal variation than did the Ministry Mounder. Soil temperatures at 10 cm depth had maxima greater than 15 degrees C for significant periods well into September in the Bracke Mounder treatment. Temperatures in both treatments approached freezing by the end of the study period. Temperatures in the Ministry Mounder treatment at 20 cm depth, Bracke Mounder humus/miner-al interface, and patch treatment 10 cm depth, a l l had similar patterns with a decreasing trend from about 14 degrees C to 4 degrees C and a diurnal range of 2-3 degrees C. Soil temperature at 10 cm depth in the control microsite dropped from ,11 degrees C to 6 degrees C over the monitoring period with l i t t l e diurnal variation. The results of the environmental monitoring project for a l l three spruce sites are summarized in Appendix C. 3.3 Biological Analysis of the biological data proved quite challenging. I n i t i a l l y , analysis of variance testing included a l l three spruce sites, with treatment and block effects being tested within sites, and the Kluskus Road pine site tested separately. However, a significant treatment x site interaction was found. This i s readily explained by the different climatic conditions each site experienced; especially the periodic high water tables, the Stewart Lake 55 and Iron Creek seedlings experienced. This appeared to have the greatest impact on seedlings planted in the patch and control treatments. Heavy, late moisture inputs from precipitation on the Iron Creek site appeared to help seedlings planted in the Sinkkila Mounder treatment. The Sinkkila Mounder treatment was the most inconsistent of a l l the treatments. This is in part explained by mechanical malfunction which varied from site to site (Hedin 1987). Differences in stock type, seedlot, and vigor (as shown in RGC testing) also added to the confusion. Analysis proceeded on a site by site basis; however, complications s t i l l arose. As mentioned earlier, experimental layout followed the randomized complete block design of FRDA 1.10. Blocking, however, does not seem to follow any s t r a t i f i e d set of conditions and appears to be merely systematic labelling as far as parameters affecting seedling performance are concerned. This is easily seen by viewing site s o i l texture and humus depth/form information presented in Appendix A in relation to block layout. This suggests that experimental layout should have followed a completely randomized design and that blocking only served to increase the estimate of the standard error by losing 1 degree of freedom. Thus, mean separation tests based on this overestimated standard error w i l l be overly cautious, and means tested as not significantly different may in fact be significantly different. Block x treatment interaction was also a problem, but could be readily explained by site conditions, which varied over the blocks and in the microsites a b i l i t y to overcome the constraint (i.e. patch treatments were more susceptible to plots with a high water table than mounded treatments). 56 3.3.1 Root Growth The 45 day assessment of root egress i s summarized in Table 7 and Figures 10, 11, and 12. On a l l three spruce sites, seedlings planted i n the deep mineral s o i l over inverted humus mounds created by the Ministry Mounder had significantly greater numbers of new roots longer than 1 cm than did seedlings planted in patch or control treatments. This was also the case for the breaking plow treatment on the Stewart Lake site (not shown in Figure 11). Seedlings planted in the shallower mounds created by the Bracke Mounder had generally greater numbers of new roots greater than 1 cm than did patch or control seedlings, however, this was not always a significant difference. Mounded seedlings also had greater numbers of new roots less than 1 cm on the Stewart Lake si t e . Seedlings for a l l treatments on the Iron Creek and Mackenzie sites had similar numbers of new roots less than 1 cm. Generally, spruce seedlings in a l l 4 treatments, on a l l three sites, had greater numbers of new root tips greater than 1 cm in length growing from the end of the-root plug than from the sides. Equal numbers of new root tips less than 1 cm were generally found on the ends and sides of the root plugs. Pine seedlings on the Kluskus Road site generally had significantly more root tips on control treatment seedlings than patch or shallow mound treat-ment seedlings. Deep mound treatment seedlings were intermediate and not significantly different from any of the other treatment seedlings. The 70 day assessment of root egress i s summarized in Table 8 and Figures 13 to 16. On the Iron Creek site both the Ministry and Bracke mound treatment seedlings had significantly greater numbers of new roots greater and less than 1 cm than did the control and patch treatment seedlings. On the Stewart Lake site the Ministry Mounder treatment seedlings had s i g n i f i -cantly greater numbers of new roots in a l l categories than did the Bracke Mounder Table 7. Mean number of new roots growing from the root plug, 45 days after planting. Means in a group followed by the same let ter do not di f fer s ignif icantly as determined by a Duncan's mean separation test (P 0.05). White_spruce _ Lodgepole pine Iron Greek Stewart Lake Mackenzie Kluskus Road Root Catagory Mean Treatment Mean Treatment Mean Treatment Mean** Treatment Side, LT 1 cm 11.06 a control 20.52 a min. ITU 26.16 a patch 22.04 a control 9.70 ab min. m. 12.22 b br. plow 25.20 a min. m. 17.16 ab deep m. 9.62 ab bracke m. 11.92 b bracke m. 16.76 b bracke m. 15.44 b patch 7.80 b patch 8.18 be patch 15.70 b control 15.38 b shal. m. 6.63 c control Side, GT 1 cm 7.04 a min. m. 5.76 a min. m. 11.32 a min. m. 3.63 b bracke m. 4.86 ab br. plow 8.00 b bracke m. 3.26 b control 4.04 b bracke m. 7.00 b control 3-04 b patch 2.26 c patch 6.34 b patch 2.18 c control End, LT 1 cm 15.14 a bracke m. 19.73 a min. m. . 15.64 a patch 10.64 b min. m. 15.46 b br. plow 14.70 a control 10.40 b control 12.32 b bracke m. 13.36 a min. I D 9.40 b patch 8.53 c control 12.54 a bracke m. 7.03 c patch End, GT 1 cm 19.64 a min. m. 8.36 a min. m. 29.32 a min. m. 15.60 a bracke m. 8.26 a br. plow 19.03 b bracke m. 9.72 b patch 4.40 b bracke m. 15.02 b patch 7.83 b control 2.42 be control 12.26 b control 1.26 c patch ** means for this site represent the total number of root tip;$ as groupings based on size and location were not made. tn •H H O cu z 4-1 o u •§ o H Control Patch Bracke M. Min. M. ZZI S i d e , L T 1 cm f \ X l S i d e , G T 1 cm E Z 2 E n d , L T 1 cm E n d , G T 1 cm Figure 10. Total root egress 45 days after planting, Iron Creek spruce site. 60 to Cu 30 -O cu 5s 30 -Control Patch Bracke M. Min. M. EZJ S i d e , L T 1 cm I V \ 1 S i d e , G T 1 cm V77A E n d , L T 1 cm fC^} E n d , G T 1 cm Figure 11. Total root egress 45 days after planting, Stewart Lake spruce s i t e . 59 Figure 12. Total root egress 45 days after planting, Mackenzie spruce s i t e . Table 8. Mean number of new roots growing from the root plug, 70 days after planting. Means in a group followed by the same letter do not differ significantly as determined by a Duncan's mean separation test (P 0.05). White_spruce Lodgepole pine Iron Greek Stewart Lake Mackenzie Kluskus Road Root Gatagory Mean Treatment Mean Treatment Mean Treatment Mean Treatment Side , LT 1 cm 47.70 a min. m. 64.58 a min. m. 108.40 a min. m. 11.80 a patch 42.24 a bracke m. 47.16 b bracke m. 87.10 b bracke m. 11.00 a con t ro l 32.38 b control 41.26 b br . plow 73.94':bc patch 8.66 a min. m. 21.38 c patch 28.98 c control 57.46 c con t ro l 15.96 d patch Side , GT 1 cm 19.60 a bracke m. 23.46 a min. m. 31.00 a min. m. 2.38 a patch 18.62 a min. m. 16.34 b bracke -m. 21.30-b bracke m. 2.14 a min. m. 11.40 b control 12.96 b br . plow 18.02 be patch 1.92 a con t ro l 6.36 c patch 8.16 c control 15.28 c con t ro l 4.98 c patch End, LT 1 cm 24.52 a bracke m. 20.94 a min. m. 48.34 a min. m. 4.94 a min. m. 22.88 a min. m. 17.80 ab bracke m. 31.14 b bracke m. 4.40 a cont ro l 5.90 b control 17.18 b br . plow 20.46 c con t ro l 3-88 a patch 5.54 b patch 13.20 c control 18.72 c patch 7.08 d patch End, GT 1 cm 42.18 a bracke m. 20.66 a min. m. 37.78 a min. m. 11.30 a cont ro l 31.26 b min. m. 15.94 b bracke m. 27.24 b bracke m. 6.88 b min. m. 10.02 C control 13.48 b b r . plow 21.26 b patch 6.74 b patch 7-78 C patch 9.58 c control 20.88 b con t ro l 3.48 d patch O 6 1 130 Control Patch Bracke M. Min. M. EZ) Side, LT 1 cm fZZA End, LT 1 cm f\Xl Side, GT 1 cm JSS End, GT 1 cm Figure 13. Total root egress 7 0 days after planting, Iron Creek spruce s i t e . Control Patch Bracke M. Min. M. V7\ Side, LT 1 cm V77A End, LT 1 cm r \ ^ l Side, GT 1 cm E?53 End, GT 1 cm Figure 14. Total root egress 70 days after planting, Stewart Lake spruce s i t e . 62 2*0 Control Patch Bracke M. Mis. M. EZJ S i d e , L T 1 cm £2g E n d , L T 1 cm 1X3 S i d e , G T 1 cm FSSJ E n d , G T 1 cm Figure 15. Total root egress 70 days after planting, Mackenzie spruce site. 30 Control Patch Min. M. EZJ S i d e , L T 1 cm E^g E n d , L T 1 cm E 3 S i d e , G T 1 cm r^g E n d , G T 1 cm Figure 16. Total root egress 70 days after planting, Kluskus Road pine si t e . and breaking plow treatment seedlings, which were similar and significantly greater than the patch and control treatment seedlings. On the Mackenzie site the Ministry Mounder treatment seedlings again had greater numbers of new roots in a l l categories than did a l l other treatment seedlings. The Bracke Mounder seedlings generally had greater numbers of new roots than did the patch seedlings, which generally had greater numbers of new roots than did the control seedlings, however, these differences are not a l l sig -nificant . By this time the number of new roots greater than 1 cm i n length was generally divided equally between the ends and sides of the root plugs. Seedlings on both mounded treatments at Iron Creek s t i l l had greater numbers of new roots greater than 1 cm in length growing from the ends of the plugs than from the sides. Pine seedlings on the Kluskus Road site generally had similar numbers of new roots in a l l categories. Seedlings in the control treatment had significantly more roots greater than 1 cm on the end of the plug than mound or patch seedlings. At this time i t was observed that many roots greater than 1 cm which had grown from the root plug ear l i e r in the season had suberized and were not t a l l i e d . The 95 day assessment of root egress i s summarized in Table 9. On the Iron Creek site a l l three mounding treatment seedlings had significantly higher root area indices than did patch or control seedlings. The seedlings planted in mounds created by the Sinkkila Mounder had a significantly higher root area index than did the seedlings planted in mounds created by the Ministry Mounder. Seedlings planted in mounds created by the Bracke Mounder had a mean root area index intermediate of the two and not significantly different from either. On the Stewart Lake site seedlings planted in the Ministry Mounder, breaking plow and Bracke Mounder treatments had s i g n i f i Table 9. Mean root area indices, 95 days after planting. Means followed by the same lett e r do not d i f f e r significantly as determined by a Duncan's mean separation test (p 0.05). S i t e Mean Treatment Iron Greek 87.948 a sink. m. spruce 85o6l4 ab bracke m. 79.432 b min. m. 62.034 c c o n t r o l 55.758 c patch Stewart Lake 80.296 a min. m. spruce 76.940 a br. plow 75.260 a bracke m. 68=742 b sink. m. 62.294 c D-180 57.712 c c o n t r o l 57.378 c patch Mackenzie 93-166 a min. m. spruce 90.166 ab patch 87.014 be D-180 86.812 be bracke m. 82.036 c c o n t r o l 74.380 d sink. m. Kluskus Road 51.086 a min. m. pine 49.776 a D-180 49.424 a V-plow 49.094 a patch 390990 b c o n t r o l cantly higher root area indices than did seedlings planted on a l l other treatments. Seedlings planted on the Sinkkila Mounder treatment had a significantly higher mean root area index than the Donaren 180, control, and patch treatment seedlings. On the Mackenzie site the difference in mean root area index between the various treatments was less well defined than on the two other sites. The Ministry Mounder and patch seedlings had the highest mean root area indices, however, the patch seedlings' mean root area index was not significantly higher than the Donaren 180 and Bracke Mounder seedlings' mean root area indices, which were not significantly higher than the control seedlings' mean root area index. The seedlings planted in the Sinkkila Mounder treatment had a significantly lower mean root area index than in a l l other treatments. The pine seedlings on the Kluskus Road site had similar mean root area indices, for a l l treatments except the control, which had a mean root area index significantly lower than the other treatments. The 95 day assessment of root system dry weights i s summarized in Table 10. On the Iron Creek site, seedlings on a l l three mounding treatments had greater root system dry weights than did seedlings on control and patch treatments. On the Stewart Lake site seedlings on the Ministry Mounder, Sinkkila Mounder and breaking plow treatments had significantly higher root system dry weights than did seedlings on the control, Donaren 180, and patch treatments. Seedlings planted on the Bracke Mounder treatment had inter-mediate root system dry weights. On the Mackenzie site differences between the various treatments were less significant. Seedlings planted in the Donaren 180, Bracke Mounder and patch treatments had significantly greater root system dry weights than did seedlings planted on the Sinkkila Mounder treatments which had the lowest root system dry weights. Seedlings planted Table 10. Summary of s e e d l i n g dry weight d a t a , 95 days a f t e r p l a n t i n g . Means f o l l o w e d by the same l e t t e r do not d i f f e r s i g n i f i c a n t l y as determined by a Duncan's mean s e p a r a t i o n t e s t (P 0 . 0 5 ) . Iron Greek Data Gatagory Mean Treatment Shoot Weight 4.630 a min. m. 4.139 ab sink. m. 4.096 ab bracke m. 3.341 b patch 3.249 b c o n t r o l Root Weight 1.186 a min. m. 1.177 a bracke m. 1.093 a sink. m. 0.792 b c o n t r o l 0.628 b patch T o t a l Weight 5.816 a min. m. 5.273 a bracke m. 5.232 a sink. m. 4.041 b con t r o l 3.969 b patch Shoot:Root 5.120 a patch Ratio 4.933 a con t r o l 4.128 a min. m. 3-978 a sink. m. 3.725 a bracke m. Stewart Lake Mean Treatment 6.699 a min. m. 5-982 ab bracke m. 5.935 ab D-180 5.735 ab br. plow 5.515 abc sink. m. 5.011 be control 4.347 c patch I.856 a min. m. 1.660 a sink. m. 1.577 a br. plow 1.485 ab bracke m. 1.078 be control 0.970 c D-180 0.793 c patch 8.369 a min. m. 7.467 ab bracke m. 6.997 ab br. plow 6.668 b sink. m. 6.541 b D-180 6.089 b c o n t r o l 4.599 c patch 6.084 a D-180 5 0667 ab patch 4.946 be control 4.257 ed bracke m. 3.909 d br. plow 3.697 d min. m. 3.689 d sink. m. Mackenzie Mean Treatment 3.372 a bracke m. 3.167 a min. m. 3.111 a D-180 3.027 a patch 2.353 b sink. m. 2.301 b c o n t r o l 1.401 a D-180 1.366 a bracke m. 1.325 a patch 1.302 ab min. m. 1.180 ab c o n t r o l 0.917 b sink. m. 4.738 a bracke m. 4.512 a . D-180 4.469 a min. m. 4.352 a patch 3.481 b c o n t r o l 3.270 b sink. m. 2.771 a sink. m. 2.583 a min. m. 2.557 a bracke m. 2.416 a patch 2.285 a D-180 2.255 a c o n t r o l Kluskus Road Mean Treatment 1.743 a D-180 1.716 a min. m. 1.680 a patch 1.606 a V-plow 1.376 a c o n t r o l 0.657 a patch 0.624 ab D-180 0.555 ab V-plow 0.512 b min. m„ 0.504 b c o n t r o l 2.367 a D-180 2.337 a patch 2.228 ab min. m. 2.161 ab V-plow 1.880 b c o n t r o l 3.432 a min. m. 3.055 a V-plow 2.924 a D-180 2.917 a con t r o l 2.578 a patch 67 on the Ministry Mounder and control treatments had intermediate root system dry weights not significantly different, however, from any of the other treatments. On the Kluskus Road site, pine seedlings on the patch treatment had significantly greater root system dry weights than did seedlings planted on the mound and control treatments. Seedlings planted on the Donaren 180 trench and V-plow treatments had intermediate dry weights, not significantly different from the other treatments. 3.3.2 Shoot Growth The 95 day assessment of seedling shoot dry weights i s summarized in Table. 10. The 95 day assessment of seedling shoot growth i s summarized in Table 11. On the Iron Creek site, spruce seedlings planted on the three mounding treatments had significantly longer 1987 leaders than did patch or control treatment seedlings. As well, seedlings planted on Ministry and Bracke Mounder treatments had significantly larger root collar diameters than control treatment seedlings. A l l three mounding treatments produced seedlings with significantly greater total seedling dry weights than control or patch treatment seedlings. A comparison of shoot:root ratios produced no significant differences among any of the treatments. On the Stewart Lake site only seedlings planted on the Donaren 180 and patch treatments had significantly longer 1987 leaders than did control or Ministry Mounder treatment seedlings. Breaking plow, Sinkkila Mounder and Bracke Mounder treatment seedlings had intermediate leader growth, not significantly different from any of the treatments. Seedlings planted on the Ministry Mounder treatment had significantly larger root collar diameters than did seedlings on the Donaren 180, control or patch treatments. Table 11. Summary of seedling shoot growth data, 95 days after planting. Means followed by the same letter do not differ significantly as determined by a Duncan's mean separation test (P 0.05). White_sp_ruce Lodgepole pine Iron Greek Stewart Lake Mackenzie Kluskus Road Data Gatagory Mean Treatment Mean Treatment Mean Treatment Mean Treatment Height (cm) 33.47 a min. m. 35.64 a D-180 27.90 a patch 24.09 a V-plow 32.75 ab s ink, ni, 35.04 ab s ink . m. 27.57 a min. m. 23.89 a patch 32.00 ab bracke m. 34.47 ab bracke m. 26.08 b D-180 23.20 a D-180 31.22 be patch 34.44 ab br . plow 25.87 b s ink . m. 22.70 ab min. m. 25.91 c control 34.31 ab patch 25.34 b bracke m. 21.45 b con t ro l 33.41 b min. m. 25.23 b cont ro l 32.98 b cont ro l 198? Leader 14.66 a min. m. 14.20 a D-180 11.89 a patch n/a growth (cm) 14.60 a s ink . m. 14.00 a patch 11.35 ab min. m. 14.05 a bracke m. 13.58 ab br„ plow 10.35 be D-180 12.38 b patch 12.84 ab s ink . m. 9.96 c s ink . m. 11.75 b control 12.63 ab bracke m. 9-75 c cont ro l 12.09 b control 9.58 c bracke m. 12.04 b min. m. Root C o l l a r 3.344 a min. m. 4.132 a min. m. 3.420 a patch 2.622 a V-plow diameter 3.224 a bracke m. 4.070 ab bracke m. 3.196 b min. m. 2.600 a patch (mm) 3.112 ab patch 4.008 ab br . plow 3.074 b D-180 2.588 a D-180 3.046 ab s ink . m. 3.820 ab s ink . m. 2.832 c con t ro l 2.168 b con t ro l 2.912 b cont ro l 3.728 be D-180 2.630 ed bracke m. 2.120 b min. m„ 3.452 c control 2.474 d s ink . m. 3.430 c patch Seedlings planted on the Bracke Mounder, breaking plow and Sinkkila Mounder treatments had intermediate diameters not significantly different from the other treatments. Seedlings planted on the Ministry Mounder treatment had a significantly higher total dry weight than did seedlings planted on the Sinkkila Mounder, Donaren 180, control and patch treatments. Seedlings planted on the patch treatment had total dry weights significantly lower than a l l the other treatments. On the Mackenzie site, seedlings planted on the patch and Ministry Mounder treatments had significantly greater 1987 leader growth than did seedlings on the Sinkkila' Mounder, control and Bracke Mounder treatments. Seedlings planted on the patch treatment also had significantly greater root collar diameters than a l l other treatments. Seedlings planted on Ministry Mounder and Donaren 180 treatments had significantly greater root c o l l a r diameters than control, Bracke Mounder and Sinkkila Mounder treatment seedlings. Only control and Sinkkila Mounder treatment seedlings, however, had significantly lower total dry weights than any of the other, treatment seedlings. A comparison of shoot:root ratios produced no significant differences among any of the treatments. On the Kluskus Road site pine seedlings on the V-blade, patch and Donaren 180 treatments were significantly t a l l e r than on the control treat-ment. Seedlings on the Ministry Mounder treatment were intermediate and not significantly different from the other treatments. Seedlings on the V-blade, patch, and Donaren 180 treatments had significantly larger root coll a r diameters than seedlings on the Ministry mound and control treatments. A comparison of shoot weights and shoot:root ratios produced no significant differences among any of the treatments. 70 3.3.3 Foliar Analysis The 95 day assessment of f o l i a r analysis i s summarized in Table 12. Foliar N concentration ranged from 0.982 to 1.440 % for spruce seedlings at Iron Creek, 1.240 to 1.464 % for spruce seedlings at Stewart Lake, and 1.130 to 1.648 % for spruce seedlings at Mackenzie. Foliar P concentration ranged from 0.164 to 0.266 % for spruce seedlings at Iron Creek, 0.144 to 0.190 % for spruce seedlings at Stewart Lake, and 0.198 to 0.262 % for spruce seedlings at Mackenzie. Iron Creek seedlings showed the most significant differences between treatments. Seedlings planted in the Ministry Mounder treatment had significantly lower N and P concentrations than seedlings planted in the patch treatment. Seedlings planted in the other treatments had intermediate values. No significant treatment differences were found at Stewart Lake. Only slight differences in N concentration values were found at Mackenzie. Foliar N concentration ranged from 1.140 to 1.4 66 % and P concentration ranged from 0.124 to 0.180 % for pine seedlings at Kluskus Road. Needle weight data is also presented in Table 12. Generally, treatment rankings were opposite those of the nutrient concentrations l i s t e d above. 3.3.4 Survival and Frost Damage Survival and frost damage were t a l l i e d in late August as part of the FRDA 1.10 Project. Results are summarized in Table 13. Survival was high on a l l three spruce sites ranging from 89 to 100 %. Frost damage was highest on patch, control and Bracke mound treatments at Iron Creek, and, control, Bracke mound, Sinkkila mound, and patch treatments at Stewart Lake. Frost damage was high on a l l treatments at Mackenzie with 40 to 63 % of a l l seedlings being affected. Table 12. Foliar analysis of 1987 leader, growth, 95 days after planting. Means followed by the same letter do not differ significantly as determined by a Duncan's mean separation test (P 0.05). Data Catagory Iron Mean Greek Treatment White spruce Stewart Lake Mean Treatment Mackenzie Mean Treatment Lodgepole pine Kluskus Road Mean Treatment N cone. {%) 1.440 a patch 1.464 a patch 1.648 a con t ro l 1.466 a cont ro l 1.252 ab control 1.390 a ' s ink. m. 1.468 ab s ink . m. 1.438 a min. m. 1.168 be s ink. m. 1.376 a bracke m. lo452 ab min. m. 1.332 a patch 1.070 be bracke m. 1.364 a D-180 1.346 ab bracke m. 1.146 a V-plow 0.982 c min. m. 1.358 a br . plow 1.292 ab patch 1.140 a D-180 1.352 a control 1.130 b D-180 1.240 a min. m. P cone. {%) 0.266 a patch 0.190 a D-180 O.262 a con t ro l 0.180 a cont ro l 0o204 ab control 0.170 a s ink. m. 0.240 a patch O.I58 ab min. m. 0.192 ab bracke m. 0.166 a cont ro l 0.238 a s ink . m. 0.142 ab patch 0.1?4 ab s ink. m. 0.166 a bracke m. 0.224 a min. m. 0.128 b V-plow 0.164 b min. m. 0.162 a patch 0.208 a bracke m. 0.124 b D-180 0.144 a br . plow 0.198 a D-180 0.144 a min. m. Weight of 0.195 a bracke m. 0.174 a D-180 0.153 a min. m. 0.492 a patch 100 needles 0.192 a s ink. m. 0.160 a bracke m. 0.126 ab s ink . m. 0.484 a D-180 (g) 0.186 a min. m. 0.158 a min. m„ 0.125 ab bracke m. 0.466 a V-plow 0.163 a control 0.154 a br . plow 0.124 ab patch 0.374 a cont ro l 0.157 a patch 0.145 a patch 0.124 ab D-180 0.367 a min. m. 0.143 a s ink. m. 0.096 b con t ro l 0.140 a control Table 13. Summary of survival and frost damage at the end of the f i r s t growing season (from McMinn and Bedford 1988) . % % Frost Site Treatment Survival Damage Iron Greek br. plow 99 1 spruce patch 98 24 control 98 16 bracke m. 97 11 min. m. 97 9 sink. m. 96 5 Stewart Lake patch 99 11 spruce D -180 98 7 br. plow 98 5 min 0 m. 97 3 control 96 22 bracke ra0 92 18 sink. m. 92 15 Mackenzie patch 100 4 0 spruce control 99 50 D -180 9 8 63 min. m. 96 52 sink. m. 94 4 9 bracke m„ 89 54 Kluskus Road min. m. 61 0 pine control 7 3 3 D -180 8 3 0-1 patch 86 0-1 V-plow 87 0-1 Survival was generally low for the pine seedlings at Kluskus Road and ranged from 61 to 87 %. Frost damage was low for the pine seedlings ranging from 0 to 3 %. 3.4 Vegetation Ingrowth and Competition A summary of the assessment of vegetation ingrowth and competition as measured by MOF in the second and third weeks of August, 1987, is presented in Table 14. Generally, the mounding and plowing treatments had s i g n i f i -cantly lower percent cover of vegetation greater than 20 cm height than did patch and control treatments. No treatment difference was observed at the Kluskus Road Site. Competition and ingrowth was greatest at the Stewart Lake site followed by Iron Creek, Mackenzie, and Kluskus Road, in descending order. 74 Table 14. Summary of the assessment of vegetation ingrowth and competition. Values sharing a common letter are not significantly different, p = 0.01 (from MacKinnon and McMinn 1988) L o c a t i o n T r e a t m e n t Total % cover vegetation > 20 cm Total % cover vegetation < 20 cm C o m p e t i t i o n I n d e x 1 Stewart Lake herbicide 5.275 a Ministry mounder 9.886 a,b breaking plow 16.180 b,c Bracke mounder 19.731c Bracke patch & fertilizer 42.840 d Donaren 47.620 d control 47.760 d Bracke patch 48.380 d 13.250 a 6.795 a 10.320 a 8.115 a 9.220 a 8.760 a 14.040 a 8.320 a 21.130 a 46.213 a 59.293 a 85.834 a 264.401 b 268.150 b 335.546 b 274.807 b Kluskus Ministry mounder V-blade Sinkkila control 4.720 a 5.280 a 7.900 a 10.490 a 4.780 a 8.780 a 10.640 a,b 17.408 b 27.916 a 16.501 a 34.044 a 43.305 a Mackenzie herbicide Bracke mounder Ministry mounder V-blade Bracke patch control 4.960 a 9.109 a,b 13.157 a.b.c 13.800 a.b.c 18.700 b,c 20.640 c 24.840 b 13.087 a 11.530 a 24.040 b 22.940 b 45.420 C 38.356 a 26.762 a 85.883 a 84.534 a 118.317a 112.496 a Iron Creek herbicide Ministry mounder Bracke mounder breaking plow Bracke patch control 4.660 a 8.180 a 11.560 a 14.575 a 26.080 b 32.340 b 11.540 a.b 6.820 a 11.100 a,b 8.350 a,b 13.660 a,b 14.660 b 14.910 a 50.394 a 49.170 a 55.739 a 171.342 b 215.358 b 1_ ... . , % cover of vegetation greater than 20 cm x average heiqht of veqetation 1 Competition Index « -p-* f ——. :— r r— 3—-re* r distance of nearest vegetation to the seedling 75 4 Discussion 4.1 Microclimate Unfortunately the climatic monitoring program (FRDA 1.25) began after the crucial period of spring root growth, and one can only extrapolate back as to what root zone temperatures might have been at this crucial time of root development. However, the variation i n s o i l thermal regimes over the different site preparation treatments monitored in this study closely matches the findings of other similar studies (Macadam 1988, Herring and Letchford 1987, Orlander 1986, Spittlehouse 1988) . The period monitored in this study seems to match phases 3 and 4 (Figure 17) described by Macadam (1988), suggesting that root zone temperatures in a l l treatments were at a maximum before the monitoring program began, and that at this time the same treatment differences observed were even greater. Based on the assumption that these studies are comparable, we can state that the mounding and plowing treatments probably reached higher root zone s o i l temperatures earl i e r than patch, trench and control treatments. We s t i l l cannot test the hypothesis that l i t t l e root growth would occur u n t i l root' zone temperatures warmed to levels above 10 degrees C, as seedling sampling did not begin t i l l 45 days after planting and we cannot accurately predict when these threshold temperatures were reached. Also, new roots which had suberized by this time were not included in the t a l l y . S o i l temperatures are especially c r i t i c a l at the time of spring planting as studies have shown seedlings to be most susceptible to moisture stress immediately after planting (Grossnickle 1988, Grossnickle and Blake 1985, 1987). Rapid, early, new root growth improves water uptake by establishing intimate soil/root contact, and by exploiting more s o i l volume. New 76 a) HYGR1C PLOT DECREE HOUR SUM BASE-10DEGC UNTRT SCALP E2 LG INV MND El SM INV MND MAY 21-25 JULY 17-21 SEPT 5-9 SEPT 10-14 b) SUBHYGRIC PLOT DEGREE HOUR SUM 900 800 700 600 500 BASE=10 DEG C 400 300 200 100 0 • UNTRT a B SCALP a,b • PLOW b,c LTJ MIN MND c.d • LG INV MND d El SM INV MND d jffL c) DEGREE HOUR SUM BASE-10 DEG C 800 700 600 500 400 300 200 100 0 MAY 21-25 JULY 17-21 SEPT 5-9 SEPT 10-14 MESIC PLOTS U • UNTRT a II SCALP a,b HTJ MIN MND b • PLOW b.c El SM INV MND c MAY 21-25 JULY 17-21 SEPT 5-9 SEPT 10-14 Figure 17. Total degree hours greater than 10 degrees C recorded at a depth of 10 cm in (a) hygric, (b) subhygric, and (c) mesic plots, by Macadam (1988). Treatments followed by a common letter are not significantly different during the July period (p less than 0.05) as determined using Tukey's HSD mean separation test. unsuberized roots can also absorb more water than older, l i g n i f i e d ones (Hunt 1987, Grossnickle and Blake 1985, 1987). The optimal root zone temperature for white spruce is approximately 20 degrees C, with 5 to 10 degrees C seen as a minimum temperature for root growth (Dobbs and McMinn 1977, Binder et a l 1987) . The temperature regimes of each site preparation treatment can be rationalized by examining the characteristics of the planting microsite created and i t s subsequent affect on s o i l thermal properties. The presence of a surface organic layer distinguishes the control treatment from a l l others. The insulating effect of the organic matter and vegetation dire c t l y prevents the incoming solar radiation from reaching the mineral s o i l below. It also helps conserve moisture, and prevent heat loss at night thus creating the cooler, stable thermal patterns observed in the control treatment and humus/mineral s o i l interface zone below the mineral s o i l mounds. The exposure of mineral s o i l by patch, V-plow, and trenching treatments allows incoming solar radiation to warm the s o i l p r o f i l e . However, the amount and depth of temperature increase is limited by the moisture content of the s o i l . This was especially evident on the Stewart Lake and Iron Creek sites which had high and fluctuating water tables. The additional draining and elevating effect of the plowing and a l l mounding treatments contributed to higher summer root zone temperatures in these treatments. The improved drainage and increased surface area of the s o i l , however, cause the increased temperature fluctuation in response to weather changes and increased night-time radiation^ thereby more rapidly lowering s o i l temperature. These treatments also react more rapidly as the radiation input declines in the f a l l . The benefits, however, of earl i e r warming of the root zone in the spring more than compensate for this sensitivity to climatic 78 conditions. 4.2 Root Egress The 45 day assessment of root egress supports the hypothesis that the numbers of new roots greater than 1 cm in length would be greatest on treatments with the warmest root zone temperatures. The mound and plowing treatments had both warmer root zone temperatures and greater numbers of new root tips greater than 1 cm in length than patch or control microsites. Andersen et a l . (1986) suggested that root elongation was suppressed more by low s o i l temperature than t i p i n i t i a t i o n . A decline in total number of new root tips, but greater numbers of roots greater than 0.5 cm in length, with increasing temperature may reflect increased u t i l i z a t i o n of carbohydrates for elongation at the expense of new t i p development. The results from the Mackenzie site (Figure 12) in which the patch seedlings had a greater t o t a l number of root tips than did the Bracke Mounder seedlings, but fewer new roots greater than 1 cm in length, support this idea. The 70 day assessment also supports this hypothesis with the mounding and plowing treatment seedlings having greater numbers of new roots greater than 1 cm in length than patch or control treatment seedlings. The 95 day assessment confirms this as well, however, v a r i a b i l i t y in success of the various treatments over the three sites can in part be explained by other factors, primarily s o i l moisture. The Iron Creek and Stewart Lake sites both had high fluctuating water tables and experienced large precipitation events in July and August. This had the greatest negative impact on seedlings planted in the patch, trench and control treatments. Some seedlings planted in the shallower mounds formed by the Bracke Mounder were also negatively affected. This is reflected in Figures 13 and 14. Seedlings in the control 79 treatments faired better than seedlings in the patch treatment for two reasons: 1) transpiration of competing vegetation may have lowered the water table i n the control treatment; and, 2) patch seedlings, while planted on the shoulder of the patch, were s t i l l planted in a lower position relative to control seedlings (Figure 6). The destructive effect of flooding on new root tips of white spruce has been demonstrated by Levan and Riha (1986) and Grossnickle (1987). Conifers studied by Lieffers and Rothwell (1986) showed limited penetration of the water table by seedling roots, no change in internal pore space, and blackened, necrotic roots near the water table. These match similar, visual observations made at time of sampling in this study. Ballard (1982) states that "root respiration, strongly affected by s o i l aeration and temperature, releases the energy needed for active uptake of nutrients across the root c e l l membranes", and is a requirement for root growth. The surge in numbers of roots greater than 1 cm in the Bracke mound treatment past the Ministry mound treatment, on the Iron Creek site (Figure 13) at the 70 day assessment may reflect an improvement in moisture condi-tions i n this microsite. Macadam (1988) found shallow inverted mounds to be the most susceptible to drying, and the high levels of input by precipitation at this time may have improved conditions considerably. Temperature monitoring at this time (Appendix C) shows that the two microsites had similar temperatures, with the Ministry Mounder being s l i g h t l y warmer. The Mackenzie site, while prone to spring flooding, was somewhat drier over the course of the growing season and thus the results in the patch, control, and trench treatments were better than at Iron Creek or Stewart Lake. The poor results obtained in the Sinkkila Mounder treatment reflect the high organic matter component and level of porosity in these mounds, 80 compared to those formed by the Ministry Mounder and to a lesser extent, the Bracke Mounder, and are. a direct result of high s o i l moisture potentials. Mound formation by the Sinkkila on this site was hampered by mechanical malfunction and the percentage of acceptable mounds reduced (Hedin 1987). The results of this site give a more representative comparison of temperature effects, without the added complication of periodic flooding. However, s o i l moisture is s t i l l a very important factor on this s i t e . Microclimate monitoring showed the Bracke mounds to have s l i g h t l y higher temperatures than the Ministry mounds on this site, however, this i s not reflected in better root growth (Figure 15). Increased root growth in mounds with greater depths of capping may reflect improved moisture holding capacity (Macadam 1988) and supports the findings of McMinn (1985b). Increased moisture in the deep mounds may have resulted in the damping of temperature increase and fluctuation by increasing the heat capacity of the s o i l in the capping. Thus, while root zone s o i l temperature is an important factor in seedling root growth, i t is not the only factor involved and s o i l moisture may play an equal i f not greater role in limiting root egress. Emphasis on root egress data should be placed on the 45 and 70 day t a l l i e s of new root tips, as root area indices measured the total root system of which new root growth was only a small fraction, and values are therefore greatly influenced by i n i t i a l plug root development. Root egress data supports the hypothesis that root i n i t i a t i o n would primarily occur from the end of the root plug. This is the result of container culture and design, with most of the root buds being located at the bottom of the plug. By the 70 day assessment spruce seedlings had comparable or greater numbers of new tips growing from the sides of the plugs as from the ends. Pine seedlings s t i l l showed greater numbers growing from the end 81 of the plug than from the sides. This may be the result of differences in species rooting patterns or the generally poor performance of the pine seedlings. 4.3 Seedling growth response Seedling growth response data support the hypothesis that there would be l i t t l e difference in f i r s t year morphological response to the different treatments. Seedling height and leader growth may reflect conditions previously present in the nursery rather than conditions present in the f i e l d . Grossnickle (1987) found shoot development of white spruce seedlings was not influenced by flooding or s o i l temperature treatments i n a controlled laboratory study. Root collar diameter is more representative of current season growth conditions (D. P. Lavender, pers. com.). Mounding treatment seedlings generally had higher total dry weights and root coll a r diameters than other treatment seedlings. Seedling f o l i a r nitrogen and phosphorus concentration data tend to support the hypothesis that there would be l i t t l e treatment differences. However, trends found within the data would have benefited from increased sampling. A comparison of nutrient concentrations with weight of 100 needles or total seedling dry weight data suggests a dilution by growth of similar nutrient contents obtained in the nursery prior to outplanting. Thus, nutrient concentrations measured at the end of the f i r s t growing season do not reflect the nutrient potentials of the various site preparation treatment microsites (McMinn, pers. com.). Ballard (1984), while trying to identify the important white spruce nutritional problems in plantations in the central interior, used f o l i a r analysis of 2 to 8 year old seedlings to overcome this 82 problem. Concentrations plotted against the weight of 100 needles or total seedling dry weight result in a negative linear trend which supports this theory. Foliar P concentration values generally followed the same ranking as N concentration values for the different treatments. No induced deficiency due to increased N a v a i l a b i l i t y was observed. 4.4 Subsequent 1988 observations Observations made during the f a l l 1988 end-of-second growing season sampling period support trends established during the f i r s t growing season. Seedlings planted i n the mounding treatments have shown a boom or bust type of performance. Those seedlings which have survived were by far the largest in terms of height and diameter. Root egress appeared to be concentrated in the inverted organic layer below the mineral s o i l capping. This i s not surprising as this layer offers excellent aeration, texture, and nutrition. Successful mounds appear to be ones with enough mineral s o i l capping to: compress the inverted organic layer, provide continued control of competing vegetation, retain moisture and not dry out completely, and, provide adequate elevation and drainage. This supports the findings of McMinn (1985b) who found that seedlings grew best and had the greatest mass of fine roots at the end of the second growing season in mounds with the deepest mineral s o i l cappings. Macadam (1988) found that in the hygric plots, large and small inverted mounds responded similarly, dropping to very low moisture levels only b r i e f l y in early September. In the subhygric plots, both sizes of inverted mounds had dropped to a level of approximately -1 bar by mid-July, but while the small mounds continued to drop to a very low level from that point, the large mounds responded more readily to moisture inputs in the form 83 of precipitation. The small inverted mounds in the mesic plots were drier ea r l i e r in the season than any other treatment. This rapid early drying of smaller mounds could have led to increased moisture stress on the newly planted seedlings. Seedling mortality in the deep mineral mounds appears to be the result of planting depth, especially with the 211 plug pine seedlings on the Kluskus Road s i t e . On deep mounds planting depth was a compromise between getting a portion of the root plug below the inverted organic layer and seedling burial such that insufficient leaf area remained above the s o i l surface. Mortality occurred where one or both of these constraints was not met. Development and testing of seedlings with a longer root plug i s ongoing (McMinn, pers. com.). Seedling mortality on the Sinkkila mounds, especially on the Mackenzie site, appears to be from excessive drying and subsequent seedling moisture stress. These mounds were among the loosest in composition of a l l mound types. This i s the result of the different mechanics of mound formation employed by the different implements. The ripper tines of the Sinkkila Mounder appear to be less effective at scooping up a mineral s o i l capping than the shovels and buckets of the Bracke and Ministry Mounders, respec-t i v e l y . The tines also tend to collect and r o l l slash under the mounds during formation (L. Bedford, pers. com.) which leads to poor ground contact. Hedin (1987) found the Sinkkila Mounder to have the least success in forming mineral s o i l capping at the Mackenzie site, and the most at Stewart Lake. This correlates well with second growing season observations with Stewart Lake seedlings doing quite well. A second season of settling seems to have improved the mound characteristics and may be required before planting on this treatment. 84 Seedlings in the patch and trench treatments appeared to have l i t t l e new root growth. Many of the seedlings appeared chlorotic, especially on the wetter plots. In some cases the lower portion of the root plug had rotted. Seedlings on drier plots were doing better, however, increased competition i s providing excessive shading. Patch seedlings have suffered from snow pressed vegetation, especially at Iron Creek. A l l indications appear to suggest that patch size i s too small to provide adequate control of competing vegetation. This i s reflected in assessment of ingrowth presented i n Table 14. While mound size i s not that much greater, seedling elevation above competing vegetation and winter press damage appears to be significant. Overall, the 1988 observations support the hypothesis that root egress i s a good, early indicator of site preparation treatment s u i t a b i l i t y and success. Treatments with good f i r s t year root egress generally had good second year seedling performance. The importance of rapid, early root growth to long term seedling performance and survival has been stressed by many authors (Binder et a l . 1987, Carlson 1986, Hunt 1987). 4.5 Weaknesses of the study Generally the study suffered from combining the objectives of a 3 year operational assessment of seedling performance with a 1 year detailed study of root egress * The logistics and compromises resulting from this miss-match led to the following: 1) the author had to rely on other agencies to collect correlating data, especially the environmental monitoring data; contract delays resulted in no data collected for the c r i t i c a l period just after planting; 2) the experimental layout followed that of the FRDA 1.10 study which resulted in an increased estimate of the experimental error; a completely 85 randomized design supplemented with matched seedling microsite data (i.e. moisture regime, aspect, planting height, competition) may have provided more usable data; 3) use of operational microsites required large numbers of samples to accurately estimate average seedling response; 4) the large sample size reduced the amount of detailed measurements l o g i s t i c a l l y possible to collect; 5) f i r s t year growth response and f o l i a r analysis may be premature and not reflect subtle treatment differences which may appear after 2 or more growing seasons; and, 6) varying degrees of burial of seedlings' root coll a r may have affected results by altering root:shoot ratios between the different treat-ments; testing buried versus non- buried seedlings on mounded microsites was not an objective of the operational study. 5 Conclusions Results of this study show the difference in root egress and perfor-mance of white spruce and lodgepole pine seedlings to various site prepara-tion treatments, on four sites representative of the backlog problem in the northern interior of B r i t i s h Columbia. Greater numbers of roots greater than 1 cm in length were found on spruce seedlings planted in mounded and plowed treatments than in control or patch treatments. This supported the hypothe-sis that numbers of new roots greater than 1 cm in length would be greatest on.treatments with the warmest root zone temperatures. Mounded and plowed treatment microsites had thermal regimes characterized by higher root zone temperatures than patch or control treatments. However, seedlings on patch and control treatments on the Iron Creek and Stewart Lake sites suffered from 86 high and fluctuating water tables. Second year observations supported the hypothesis that root egress is a good early indicator of site preparation s u i t a b i l i t y and success. 6 Practical Applications The results of this study have yielded the following practical applica-tions : 1) On spruce sites similar to those studied, mounding or plowing treatments should be prescribed. Patch or trench treatments which result in a depressed planting position should be avoided, especially where high or fluctuating water tables are present. 2) Measurement of root egress can be used as a good early indicator of site preparation treatment s u i t a b i l i t y and success. 3) Future studies on root egress over various site preparation treat-ments should be limited in size to allow detailed measurement of new roots and sampling at 1 week intervals throughout the growing season. Microsite monitoring must begin at or before time of planting and continue throughout the growing season. Seedling data must be accompanied by specific microsite description data, including moisture regime, planting height and competition. 4) Design of machines capable of consistently producing inverted mineral s o i l over humus mounds, with greater than 10 cm mineral s o i l capping, should be encouraged. 5) Mounds with a loose consistency may y i e l d better seedling perfor-mance i f allowed a f u l l season to settle before planting. Further studies are needed to address this point. 87 Bibliography Andersen, C. P., E. I. Sucoff, and R. K. Dixon. 1986. Effects of root zone temperature on root i n i t i a t i o n and elongation in red pine seedlings. Can. J. For. Res. 16:696-700. Armson, K. 1958. The effect of two planting methods on the survival and growth of white spruce in eastern Ontario. For. Chron. 34:376-379. Ballard, T. M. 1982. Soil interpretation for forest f e r t i l i z a t i o n , p. 152-167 in. Proceedings of the B. C. s o i l survey workshop on s o i l inter-pretations for forestry. T. Void (Ed). BCMOE, ADP Tech. Paper 6, Land Mgmt. Report No. 10. Victoria BC. Ballard, T. M. 1984. Nutritional demands of planted spruce. Dept. So i l Sci. and For. Resources Mgmt. Univ. of Bri t i s h Columbia. 16 p.' Ballard, T. M., T. A. Black, and K. G. McNaughton. 1977. Summer energy balance and temperatures in a forest clearcut i n southwestern B r i t i s h Columbia, i n . Sixth B r i t i s h Columbia Soil Sci. Workshop, p. 74-86. B.C. Min. Agri., Victoria. Bedford, L. 1986. Appraisal and development of backlog reforestation mechanical site preparation systems. FRDA Project 1.10 Proposal. BC MOFL, Victoria, BC. 7 p. .Binder, W. D., D. L. Spittlehouse, and D. A. Draper. 1987. Post planting studies of the physiology of white spruce 1984-1985. MOFL Progress Report No. 5. 94 p. Bowen, G. D. 1970. Effects of s o i l temperature on root growth and on phosphate uptake along Pinus radiata roots. Aust. J. Soil Res. 8:31-42. Burdett, A. N., L. J. Herring, and C. F. Thompson. 1984. Early growth of planted spruce. Can. J. For. Res. 14:644-651. Butt, G. 1986. Plantation failure and backlog rehabilitation in the Sub-boreal spruce and Boreal black and white spruce zones in the northern interior of Bri t i s h Columbia: A problem analysis. MOFL FRDA Internal Report. Victoria, BC. 129 p. Carlson, W. C. 1986. Root system considerations in the quality of l o b l o l l y pine seedlings. South J. Appl. For. 10:87-92. Coates, D. and S. Haeussler. 1984. A guide to the use of mechanical site preparation equipment in north central B r i t i s h Columbia. BC MOFL, Victoria. Handbook. 55 p. Corns, I. G. W. 1984. Interpretation of site factors for mechanized site preparation, p. 40-41 in Proceedings of the 1984 mechanized s i l v i c u l -ture workshop. Can. For. Serv. Info Report NOR-X-272. 47 p. 88 Corns, I. G. W. and R. M. Annas. 1984. Ecological s l a s s i f i c a t i o n of Alberta forests and i t s application for forest management, p. 40-52 in Forest c l a s s i f i c a t i o n at high latitudes as an aid to regeneration. USDA For. Serv., Tech. Report PNW-177. 56 p. Dobbs, R. C. 1972. Regeneration of white and Engelmann spruce: A l i t e r a -ture review with specific reference to the B r i t i s h Columbia interior. PFRC, Can. For. Serv., Info. Report BC-X-69. 77 p. Dobbs, R. C. and R. G. McMinn. 1977. Effects of scalping on s o i l tempera-ture and growth of white spruce, i n . Sixth Br i t i s h Columbia Soil Sci. Workshop, p. 66-73. BC Min. Agri., Victoria. Edlund, L. 1979. Mineral mound and humus mound methods: two alternative s o i l scarification methods applied in forest land i n northern Sweden. IUFRO S3.02.00 Moscow, 10 p. Edlund, L. and F. Jonsson. 1986. Swedish experience with ten years of mounding site preparation. IUFRO SI.05.12. Grand Prarie, Alta. and Dawson Creek, BC. 8 p. Fryk, J. 1986. Adapted site preparation i n Sweden. IUFRO SI.05.12 Dawson Creek, BC 19 p. Grossnickle, S. C. 1987. Influence of flooding and s o i l temperature on the water relations and morphological development of cold-stored black spruce and white spruce seedlings. Can. J. For. Res. 17:821-828. Grossnickle, S. C. 1988. Planting stress in newly planted jack pine and white spruce. 1 Factors influencing water uptake. Tree Physiology 4:71-83. Grossnickle, S. C. and T. J. Blake. 1985. Acclimation of cold-stored jack pine and white spruce seedlings: effect of s o i l temperature on water relation patterns. Can. J. For. Res. 15:544-550. Grossnickle, S. C. and T. J. Blake. 1987. Water relations and morphological development of bare-root jack pine and white spruce seedlings: seed-li n g establishment on a boreal cut-over s i t e . For. Ecol. Manage., 18:299- 318. Hackinen, C. 1987. Soil texture and humus depth/form site profiles for FRDA 1.10 sites. Internal MOFL Report to L. Bedford. 19 p. Hedin, I. B. 1987. Fie l d assessment of inverted humus mounds produced by three site preparation implements in north central Br i t i s h Columbia. FERIC Special Report No. SR-44. 38 p. Heninger, R. L. and D. P. White. 1974. Tree seedling growth at different s o i l temperatures. Forest Sci. 20:363-367. Herring, L. J. and R. A. Letchford. 1987. Assessment of treatment options for reforestation of NSR backlog in the boreal region of B. C. EP 986.00 Est. Report No. 2, Exp. Phase No. 1. 64 p. 89 Hooge, B. 1987. Red Rock Nursery and Research Centre, research seedling assessment procedures and assessment summary. MOFL Internal Report. 13 p. Hunt, J. A. 1987. Mechanical site preparation. Part II - A literature review of some biological aspects of site preparation. Swedish Univer-s i t y of Agricultural Sciences. Department of Silviculture. Master of Science Thesis. 35 p. Kramer, P. J. and T. T. Kozlowski. 1979. Physiology of woody plants. Acadamic Press. New York. 811 p. Levan, M. A. and S. J. Riha. 1986. Response of root systems of northern conifer transplants to flooding. Can. J. For. Res. 16:42-46. Lieffers, V. J. and R. L. Rothwell. 1986. Effects of depth of water table and substrate temperature on root and top growth of Picea mariana and Larix laricina seedlings. Can. J. For. Res. 16:1201-1206. Lopushinsky, W. and M. R. Kaufmann. 1984. Effects of cold s o i l on water relations and spring growth of Douglas- f i r seedlings. Forest Sci. 30:628-634. Macadam, A. 1986. Effects of mechanical site preparation treatments on s o i l temperature, s o i l moisture, and seedling establishment in the sub-boreal spruce zone. BC MOFL, internal document. 8 p. Macadam, A. 1988. Response of s o i l climate in the SBSe subzone to microsite alteration. Proc. Northern Silviculture Committee Feb. 2-3, 1988. Prince George, BC. (In press). MacKinnon, A., L. Bedford and J. Maxwell. 1987. A guide to the use of mechanical site preparation equipment in north central Br i t i s h Colum-bia. Second Edition. BC MOFL, FRDA Report 002. 63 p. MacKinnon, A. and R. G. McMinn. 1988. Response of vegetation to mechanical site preparation treatments in north central B r i t i s h Columbia, p. 19-23 i n . Vegetation competition and responses: Proceedings of the thi r d annual vegetation management workshop. Vancouver, BC. FRDA Report 026. McLeod, A. and M. Osberg. 1986. Assessment of the effectiveness of mechani-cal site preparation techniques on backlog sites in the SBS and BWBS zones. Working plan, FRDA Project 1.25. BC MOFL, Prince George, BC. 5 p. McMinn, R. G. 1982. Ecology of site preparation to improve performance of planted white spruce in northern latitudes, i n . Forest regeneration at high latitudes: experiences from northern Br i t i s h Columbia. US For. Serv., Pacific Northwest For. and Range Exp. Station, Misc. Report No. 82-1:25-32. 90 McMinn, R. G. 1984. Use and development of site preparation equipment, p. 2-7 i n . Proc. of the 1984 mechanized si l v i c u l t u r e workshop. Can. For. Serv. Info. Report NOR-X-272. 47 p. McMinn, R. G. 1985a. Mechanical site preparation and spruce performance. presented at "Interior spruce seedling performance: state of the art". Northern S i l v . Com. Sem., Prince George, BC. 6 p. McMinn, R. G. 1985b. Effect of various depths of mineral s o i l cappings on the performance of white spruce seedlings planted i n inverted humus mounds: implications for design engineers and machine operation. IUFRO S3.02.01. Jasper, Alta. 5 p. McMinn, R. G. 1988. Mechanical site preparation options i n north central Bri t i s h Columbia. Proc. Northern S i l v . Com., Feb 2-3, Prince George, BC (in press) McMinn, R. G. and L. Bedford. 1988. Establishment and progress report of 1986 t r i a l s to determine biological effectiveness of mechanical site preparation equipment. Unpublished draft summary. MOFL, Victoria. 24 P-Nielsen, K. F. and E. C. Humphries. 1966. Effects of root temperature on plant growth. Soils and F e r t i l i z e r s 29(1):l-7. Orlander, G. 1986. Effect of planting and scarification on the water relations i n planted seedlings of scots pine. Studia Forestalia Suecica 173, 17 p. Parolin, R. W., A. Read and R. G. McMinn. 1981. Operational t r i a l of a spot s c a r i f i e r , in Forest regeneration. Proc. ASAE Sym. on Eng. Sys. for For. Regen., ASAE Pub. 10-81. 37 6 p. Robertson, R. G. and R. W. Young. 1988. Tree planting manual. Nova Scotia Dept. of Lands and Forests. Amherst, NS. 52 p. Running, S. W. and C. P. P. Reid. 1980. Soil temperature influences on root resistance of Pinus contorta seedlings. Plant Physiol. 65:635-640. SAS Institute Inc. 1985. SAS User's Guide: Statistics, Version 5 Edition. Cary, NC: SAS Institute Inc., 1985. 956 p. Simpson, D. G. 1985. B. C. Ministry of Forests root growth capacity test. MOFL Internal Document. 3 p. Smith, C. R. 1984. Status of mechanization of s i l v i c u l t u r e in Canada, p. 41-49 i n . Mechanization of s i l v i c u l t u r e : increasing quality and productivity. Proc. CPPA/CFS Sem. On Mech. of Silv., Thunder Bay, Ont. Sept. 17, 1984. . Soderstrom, V. 1981. Site preparation. P. 17-20 in Forest regeneration at high latitudes: experience from northern Sweden. USDA For. Serv., Tech. Report PNW- 132. 39 p. 91 Spittlehouse, D. L. 1988. Draft - Progress report EP 966: Microclimate measurements. MOFL Res. Branch. Victoria, BC. 13 p. Stahl, P. H. 1984. How to choose site preparation methods based on site c l a s s i f i c a t i o n , p. 53-56 in Forest c l a s s i f i c a t i o n at high latitudes as an aid to regeneration. USDA For. Serv., Tech. Report PNW-177. 56 p. Sutherland, B. J. 1986. Standard assessment procedures for evaluating s i l v i c u l t u r a l equipment: A handbook. GLFC, Can. For. Serv., Sault Ste Marie. 96 p. Sutherland, B. J. 1987. S i l v i c u l t u r a l equipment assessment: The need for a common approach. Presented at CPPA Woodlands Sec. Meeting, March 1987. 6 p. Sutton, R. F. 1975. Biological aspects of mechanized regeneration, i n Mechanization of si l v i c u l t u r e i n northern Ontario symposium. Dept. Envt., Can. For. Serv., Sault Ste Marie, Ont. Symp. Proc. O-P-3: 98-122. Sutton, R. F. 1984. Mounding site preparation: evaluation of jack pine outplantings in a boreal Ontario study. Can. For. Serv., GLFRC, Sault Ste. Marie, Ont. COJFRC Jack Pine Symp. Proc. O-P-12: 66-77. Van Damme, L. 1987. Preliminary results of the Ontario mounding t r i a l s . Presented to the COFRDA Res. and Dev. Sub-Committee, OMNR Internal Report. 15 p. von der Gonna, M. and D. P. Lavender. 1987. Root egress of white spruce and lodgepole pine seedlings in mechanically prepared and untreated plant-ing sites. Working plan, FRDA Project 1.24. Dept. For. Sci, UBC. 27 P-( Appendix A Soil texture and humus form/depth (MOF internal report submitted to Lome Bedford, under contract, by Coleen Hackinen 1987) 93 A.l Iron Creek A.1.1 Humus form Humus forms were a l l found to be moders, with the exception of Plot A4 in the northern corner of the site which was c l a s s i f i e d as a mor. A.1.2 Humus depth Humus depths ranged from 10 to 52 cm across the 20 plots examined. As shown in Figure A.l, very deep organics (range 26 to 37 cm) were found on the northern edge of the site (A Blocks) and were generally associated with a high water table (above or near the organic/mineral s o i l interface at time of sampling). A small pocket of deep organic material was present in the centre of the site (Plot D7) where the humus depth reached 52 cm. Relatively thick organics were found on the western portion of the site (B Block) as well as the southwesterly corner (Plot E10), where humus depths ranged from 16 to 25 cm. There was a tendency for the organic layer depths to decrease southward through B Block. Humus depths in the remainder of the site (C and D Blocks, Plots E l to E9) were relatively uniform and ranged from 10 to 18 cm depth. A.1.3 Soil texture Profile description and sample retrieval was complicated by a high water table at time of sampling. When the mineral s o i l was below the water table, i t was necessary to reach below the water surface and retrieve mineral s o i l as a 'grab sample'. In order to allow hand texturing, the saturated sample required several days of air-drying. Textures i n the B horizons were dominantly clay loams with some s i l t y clay loams identified in the southwestern corner of the site (Plots E9, E8, Bll) . Most profiles displayed reasonably well developed Ah horizons. Textures in the A horizons were found to be s i l t y clay loams on the southern portion of the site (Blocks D and E), and clay loams on the northern portion (Blocks A, B, and C), with the exception of Plot B l l where a loam A horizon was present. Mound textures were dominantly clay loams, with some s i l t y clay loams and loams. The mound tended to reflect the dominant horizon texture as influenced by the degree of mixing of mineral and organic (or Ah) material. Figure A . l Humus depth c l a s s e s , Iron Creek s i t e . to 95 A.2 Stewart Lake A.2,1 Humus form Humus forms were a l l found to be moders (mormoders and leptomoders). A.2.2 Humus depth Humus depths ranged from 9 to 24 cm. Although some v a r i a b i l i t y was probably a result of machine site preparation effects, humus depth appeared to be closely related to topography. Wetter sites (receiving areas) tended to display thicker organic horizons (western and southern portions of s i t e ) , as shown in Figure A.2.1. A.2.3 Soil texture B horizons were dominated by s i l t y clay loams and clay loams, with some pockets of s i l t y loams. S i l t y clay loams were found along the northeast and northwest edges of the site and clay loams were dominant in the wetter areas (southern and western portions). Some so i l s contained substantial amounts of what were considered to be very fine coarse fragments (greater than 2 mm). Since s o i l texture refers to the less than 2 mm mineral fraction, these fragments were ignored during hand- texturing. In the absence of refined measurement techniques (ie. sieve) i t i s very d i f f i c u l t to determine the correct texture c l a s s i f i c a t i o n of these s o i l s . A horizons were generally quite thin (less than 5 cm) or absent. A horizon texture was variable and appeared to depend to a large extent on the form and degree of development (ie. Ae horizons - s i l t y loam or s i l t y clay loam; Ah horizons - loam, s i l t y loam, clay loam, or s i l t y clay loam) . Mound texture appeared to depend mainly on the depth of the scalp, which determined the proportion of organic and mineral s o i l (Ah, B and/or C horizons) present i n the mound, and the degree of mixing of these materials. S i l t y clay loam and s i l t y loam textures were found in mounds composed of B and C horizon material. Mounds dominated by B horizon s o i l generally reflected the texture of the B horizon (clay loam, s i l t y loam, s i l t y clay loam). Where A and B horizon s o i l were dominant in the mound, s i l t y loam and s i l t y clay loam textures prevailed. Some mounds, especially those with s i l t y loam textures, showed evidence of wind erosion (loss of fines) where a capping of coarse fragments was present on the mound surface. On mounds with higher clay content, evidence of erosion was less obvious. It appeared that the clays were acting as a "glue" to form larger, less erodible peds. BLOCK 2 BLOCK 1 ,.«;..—•.r.-i--.-.r--.»..-.-<3 BLOCK 3 BLOCK 4 Humus Depth 10 cm 11 - 15 era BLOCK 16 - 20 era 21 - 24 era nil B^iliiifcillilill // // // // Stnkkll* sound (*D - A-6 3-4 C-3 D-7 O l Sinkkila sound - n~7 3-3 C-2 D-10 t-3 S.C. Ministry Mounder -A-10 8-1 C-7 D-a E-6 > I I 1 » H > » 1 1 X X | ( DR BY: M.G..R.W. Bracke pitch C+f) ftneke Pitch Bracke Bound• I f t iMng Flow Donaren 160 *=«—*-) Untreated Herbicide HA In Road Windrows Biological Plots Block ttuMbei Plot Huaber • f * Feit l l lzed M l Treatacnti S 3-13 S.t. 873J -A-3 fl-6 C-6 0-1 £ -8 -A-2 B-7 C-6 D-2 E-9 -A-S B-3 C-10 D-4 E-2 -A-4 B-Z C-8 D-9 £-4 -A-tt B-S C-J D-5 E-10 - A - l B-10 C-9 0-3 E-5 -A-9 B-9 C-l D-6 E-7 STEWART LAKE BIOLOGICAL PLOTS DATE 86-06-27 Figure A.2.1 Humus depth classes, Stewart Lake Site. BLOCK 1 BLOCK BLOCK 3 BLOCK 4 S o i l T e x t u r e : B H o r i z o n S i l t y C l a y Loam S i l t y Loam C l a y Loam BLOCK 5 .. It * X > \ > V K K U J I A-tf<->0^", / Slnkkll* »oynd ( + F> - A-6 3-; C-3 0-7 E - l Slnfcfcll« »pund - A-7 5-1 C-2 D-10 £ - 1 B.C. Mlnlittx Mounder -A-10 B-l C-7 D-8 E-6 Bracke patch («T> -A-3 fl-& C-4 D-l £-8 -A-2 B-7 C-6 D-2 E-9 -A-S B-8 C-10 D-i t-2 -A-4 B-2 C-8 D-S t-4 •A-B B-5 C-5 P-5 r '0 - A - l 8-10 C-9 D-l -A-9 B-9 C-l D-6 E-7 Bracke Patch Bracke nound -Broking Flow Don*ren 180 ' Urn re*ted Herbicide Main Ro.id - - - - -Wind to.«a i x i • i Biologic*! Plots A Block Nu*ber A Plot N . u b f r 1 • F - f r t i U U f J M l T r ^ C a c n o S 1-11 S . L . B. 'SJ DR BY: MG..R.W. STEWART LAKE BIOLOGICAL PLOTS DATE 86-06-27 F i g u r e A.2.2 S o i l t e x t u r e o f the B h o r i z o n , S t e w a r t Lake s i t e . 98 A.3 Mackenzie A.3.1 Humus form Humus forms at the Mackenzie site included saprimulls, moders and mors. Saprimulls (profiles with thick Oh and thin or absent Ah(g) horizons) were found i n wet pockets at the western extremity and northeast corner of the si t e . Mors and moders were found i n alternating bands along the east-west axis as shown i n Figure A.3.1. Humus form appeared to correspond to topo-graphy in that saprimulls were generally found in depressions, moders on slope toes and mors on lower slopes. A.3.2 Humus depth Humus depth was highly variable, ranging from 2 cm to more than 38 cm. Some v a r i a b i l i t y may be attributed to previous site disturbances resulting from logging, since some areas contained considerably more slash than others. Very thick deposits of organic material (greater than 2 6 cm) were found in the northeast corner of the s i t e . The thinnest organic layers (less than 11 cm) occupied an area to the southeast, as well as along "a band extending from the third to ninth transects, as shown in Figure A.3.2. A.3.3 Soil texture B horizon textures were dominantly s i l t loams, with some pockets of finer textured soi l s ( s i l t y clay loams, clay loams, and s i l t y clays), as shown i n Figure A.3.3. A horizons were generally very thin or absent. Textures of the A horizons were extremely variable, and included: s i l t y clay loams, s i l t y loams, s i l t s , clay loams, sandy clay loams, loams and s i l t s . Mounds which contained inorganic s o i l were sampled for hand texture analysis, however, many mounds consisted dominantly of organic material. Only 12 mound texture determinations were possible from the 25 plots sampled. Of these, five were found to be s i l t y loams, three s i l t y clay loams, two s i l t y clays, one s i l t and one sandy clay loam. Mound textures appeared to reflect the texture of the dominant horizon in the mound as influenced by the degree of mixing with organic materials. Hillside Humus Form S a p r i r a u l l V - l l a d t S l n k k l l * Hound H l n l a t r y Hound Donaren 1800 (Sera) Donaren 1S0O (Turrow) Untreated H e r b i c i d e Untreated Large Stock Brack* Hound Bracke Fatch • -10, •-a. »-5, a-6. t-i. . »-i, »-'. «-'. »-;, »-J, , C-J c-io, C-5. C-J, c-s. c-i, c-». , 0-5, , 0-4, D-9, 0-8, D-7, , o-3. D-10, D-6, 0-1, 0-1. , is , t - J E-10 E-9 £ - 4 £-« £-2 E-o £-7 E - l Treataent I 8. S 312 - 2*0 S.L. 3956 (TH) A l l other t r e a t a e n t * S 1-13 S.L. 291(4 (BC) DR BY: Moder Mor M.G.. R.W. MCKENZIE BIOLOGICAL PLOTS DATE 86-06-27 F i g u r e A.3.1 Humus f o r m , M c K e n z i e s i t e . 10 Hillside 0 - 10 cm MAI 11 - 20 cm V-8lade S i n k k i l a Mound H l n l i t r y Houn4 Donarca 180D (B e r t ) Oonarco 1800 (furrow) Untreated H e r b i c i d e Untreated U r g e Stock Bracke Hound Brecke Patch • A-6, 6-10, C-J, 0-5, E - J • A-2, 8-8, - A-5, 0-5, • A - l , B-6, - »-». 8-2. - A-10. B-l • A-», »-9, • A-J, B-«, • A-fl, 6-7, • A-9, B-J, C-10, D-«, E-5 C-5, 0-9, t-10 C-». 0-8, £-9 C-9, 0-7, E-« C-J, D-). t - J C-6, 0-10, t-1 C-J, 0-6, E-6 C - l . D-J, E-7 C-7, 0-1, £-1 Treatnent I 8. S 312 -i 2*0 S.L. 3956 (TH) A l l other treetaenta S 3-13 S.L. 291*4 («C) 21 - 25 cm 26 cm + DR BY: M.G..R.W. MCKENZIE BIOLOGICAI PI OT.S DATE 86-06-27 Figure A.3.2 Humus depth, McKenzie s i t e . Hillside V-Blade S i n k k i l a Hound H l n l s t r y Hound Donaren 10OD (Bera) Donaren 1800 (Turrow) Untreated Herbicide Untreated Large Stock Bracke Hound Brecka Patch B-10, C-J, D-J, t - J C-10. D-«, £-! 0-5, C-5, 0-9, 8-10 - A - l , B-6, C-4, D-8, t-9 - A-J, 8-1, C-9, 0-7, l - i - A-10, 8-1, C-7, 0-J, t-8 -9, C-6, 0-10, E-2 -», C-J, 0-6, t-6 -7, C - l , D - l , t-7 - J . C-7, 0-1, t-1 - A-6, - A - l , - A-5, - A-J, • A-J, • A-9, Treataent I J . S 312 - 1*0 S.L. 3956 (TH) A l l other t r r e t a - n t a S 3-13 S.L. 29144 (AC) Clay Loam S i l t y Clay Organic horizons very deep - B horizons could not be r e t r i e v e d to a l l o w texture a n a l y s i s . DR BY: M.G.. R.W. MCKENZIE RIOLOGICAL PLOTS DATE 86-06-27 Figure A.3.3 S o i l texture of the B h o r i z o n , McKenzie s i t e . 102 A.4 Kluskus Road A.4.1 Humus form The humus forms present on this site were found to be moders (dominantly mormoders) and mors. As shown in Figure A.4.1, moders occupied a band along the northern boundary of the s i t e . Moving south from this band the humus forms gradually changed to mors. The transition from moder to mor humus form roughly coincided with topographical characteristics in that the moders occupied a position of sl i g h t l y higher elevation. Mors were found on the slope and bench located south of the moders. A.4.2 Humus depth The depth of organic horizons (L, F, H and 0) ranged from 3 to 17 cm. The thickness of the humus horizons was lowest in the northeast corner of the site, as shown in Figure A.4.2. The deepest organic profiles were located in the centre of the site along the southern boundary. Pockets of moderately deep organics (11 - 15 cm) were found to the east and west and were associated with a relatively high water table. A.4.3 S o i l texture The texture of the B horizons were dominantly s i l t loams, however, pockets of sandier soils (sandy clay, sandy clay loam, and sandy loam) were found to the northwest and northeast, as shown in Figure A.4.3. A horizons in the s o i l profiles examined were either absent or very thin (less than 2 cm). So i l textures in the mounds produced by the Ministry Mounder were highly variable, both within and across plots, and included s i l t y clay loams, loams, sandy loams, and s i l t y loams. The mound textures were not necessarily representative of the texture of the underlying B horizon. This may have been caused by two factors. F i r s t l y , the degree of incorporation of organic matter into the mineral s o i l was variable (both within and across plots). Organic matter would tend to bias the hand texturing result toward higher s i l t content. Secondly, some mounds were very dry and showed evidence of wind erosion in that the fines had been removed, leaving a cap of coarse fragments on the surface of the mound. Some attempt to overcome the effects of this additional variable was made by sampling s l i g h t l y below the coarse material on the mound surface but above the underlying organic layer. 9 y Humus Form H l n l a t r r Hound -•-Blade -S i n k k i l a fetch. - A - J . 8 - 1 . C - 6 , 0 1 , t-6 Donarao 1 8 0 0 T~ - A - ; . 8 - i , C - 7 . O - 3 , t -2 Donaren 1 8 0 0 0 - A - 6 . 8 - 3 , C-J, D- 5 , t-J Untreated - A - * , 8 - 8 , c-s. D- C-l A l t e r n a t e Stock - A - l , 8 - 6 , 8 , C -4 rerun.<d A - 2 , 8 - 5 , c-», 0 - 7 , C -6 Treatment * 7 , S 3 - 1 3 S L. 8 3 6 1 A l l o t l i e r t r e a t a e n t a 81 2 - 1 1 S.L. 0 5 7 4 Moder Mor DR BY: M.G..R.W. K L U S K U S DATE BIOLOGICAL PLOTS 86-07-21 Figure A.4.1 Humus form, Kluskus Road s i t e . Humus D e p t h H l a l a t r y Hound - A-3. 8-7, c - i . 0-4, t-7 r-Blada • A-e, »-», C-3, 0-1, l-i S i n k k i l a Fetch - A-S, 1-1, C-4, 0-1, l-l Oo«tc«Q 1800 7~ - A-', l - l . C-I. 0-3, t-1 Oonercn, 1800 (X - A-4. 1-3, C-J. 0-5, l-l Untreated - A-4, 8-8, C-3. 0-6, e-l A l t e r n a t e Stock - A - l , 8-6, C-2. 0-8, 1-4 r e c t l l l t e d A - l , 8-3, c-«, 0-7, t-4 Treatment / 7, S 1-11 S l . 81(1 A l l o t l i e r t r e a t a e n t e n 2-11 S.L. 0374 0 - 5 cm 6 - 10 cm 11 - 15 cm 16 - 20 cm • R BY M.G..R.W. K L U S K U S DATE BIOLOGICAI PLOTS 86-07-21 F i g u r e A.4.2 Humus dep t h c l a s s e s , K l u s k u s Road s i t e . o S o i l T e x t u r e : B H o r i z o n Sandy c l a y , Sandy c l a y loam, Sandy loam S i l t loam, S i l t , Loam H l n t a t r ? MounJ - A - J , B-7, c - i , D-«, 1-7 V-Sl.de - A-», »-«, C-J, D - l , t - J S l n k k . l l . P i t c h - A - J , l-I, C-6. 0-1. t - J Donates 1800 7~ - A-7, 1-1, c - l , U-J, 1-1 Donaren 1B0D 6? • A-6, B-J, C-J, 0-3, t - J Untreated - A - 4 , B-B, C-J, 0-6. t-1 A l t e r n a t e Stock - A - l , B-6, c - l . D-J, t-« P e t t l l l i e d A-!. B-J, c-«. 0-7, t-6 T r e a t . r n t I 7. S J-13 S L. 8561 A l l other t r e . t . e n t . PI 1-11 S.L. 0J7« S i l t y c l a y loam DR BY: M.G..R.W KLUSKUS DATE BIOLOGICAL PLOTS 86-07-21 F i g u r e A.A.3 S o i l t e x t u r e o f the B h o r i z o n , K l u s k u s Road s i t e . o 106 Appendix B Fi e l d assessment of inverted humus mounds (Hedin 1987) The distribution of mound classes for each implement i s presented in Tables B.l - B.3. Table B.4 compares mounding success by machine and by si t e . Average mound dimensions of acceptable mounds for each implement i s presented in Tables B.5 - B.7. Table B.8 presents ground contact assessments within acceptable mound classes for each implement. Table B . l . Distribution of mound classes - Ministry Mounder (from Hedin 198?). Fori SI. John Dawson Creek Mackenzie Vanderhool Mound class Avg no. % of Avg no. % ol Avg no. % ol Avg no. % of per total per total per total per total transect transect transect transect Greater than or equal to 20 cm mineral soil in cap over inverted organic layer 50 25.0 12.7 63.3 93 46.5 3.1 15.5 14-19 cm mineral soil in cap over inverted organic layer 4.2 21.0 3.9 19.4 3.7 18.5 4.3 21.5 10-13 cm mineral soil in cap over inverted organic layer 3.2 16.0 1.3 6.6 2.7 13.5 5.5 27.5 6-9 cm mineral soil in cap over inverted organic layer 1.6 8.0 0.8 4.1 1.1 5.5 3.6 18.0 3-5 cm mineral soil in cap over inverted organic layer 0.4 2.0 0.2 1.0 0.6 3.0 1.8 9.0 Greater than or equal to 5 cm well-decomposed inverted organic layer over undisturbed organic 1.4 70 0.1 0.5 1.2 6.0 0 0 Acceptable 15.8 79.0 19.0 94 9 18.6 93.0 18.3 91.5 Less than or equal to 2 cm mineral soil in cap over inverted organic layer 0 0 0 0 0.1 0.5 0 0 Mineral cap over mineral soil 0 0 0 0 0.1 0.5 0 0 Inverted organic mound 0.5 2.5 0 0 0.5 2.5 0.3 1.5 Organic mound, not inverted 1.1 5.5 0.1 0.5 0.2 1.0 0.6 3.0 Mineral over undisturbed organic 0.7 3.5 0.6 3.1 0.1 0.5 0 0 Organic over mineral, not inverted 0 0 0 0 0.1 0.5 0 0 Vertical mound, not overturned 0.7 3.5 0.2 1.0 0 0 0 0 No mound 1.2 6.0 0.1 0.5 0.3 1.5 0.8 4 0 Unacceptable 4.2 21.0 1.0 5.1 1.4 7.0 1.7 8.5 Total 20.0 100.0 20.0 100.0 20.0 100.0 20.0 100.0 Averages and percentages are calculated Irom original data and therefore there may be discrepancies because of rounding. T a b l e B . 2 . D i s t r i b u t i o n o f mound c l a s s e s - S i n k k i l a ( f r o m H e d i n 198?). Fort St. John Dawson Creek Mackenzie* Mound class Avg no. per transect %ol total Avg no. per transect %ol total Avg no. per transect %ol total Greater than or equal to 20 cm mineral soil in cap over inverted organic layer 0.1 0.5 0.6 3.0 0 1 0.4 14-19 cm mineral soil in cap over inverted organic layer 0.6 30 3.7 18.5 0.1 0.5 10-13 cm mineral soil in cap over inverted organic layer 36 18.0 6.2 31.0 0.6 2.9 6-9 cm mineral soil in cap over inverted organic layer 5.2 26.0 3.4 17.0 1.5 7.5 3-5 cm mineral soil in cap over inverted organic layer 4.8 24.0 1.8 9.0 2.2 110 Greater than or equal to 5 cm well-decomposed inverted organic layer over undisturbed organic 2.1 10.5 0.2 1.0 4.4 22.0 Acceptable 16.4 82.0 15.9 79.5 8 9 44.3 Less than or equal to' 2 cm mineral soil in cap over inverted organic layer 0.1 0.5 0.5 2-5 0.2 1.0 Less than 5 cm well-decomposed inverted organic layer over undisturbed organic 0 0 0 0 0.1 0.4 Inverted organic mound 1.3 6.5 0.3 1.5 1.1 59 Organic mound, not inverted 0.7 3.5 1.6 8.0 5.3 26.5 Organic over mineral, not inverted 0 0 0.1 0.5 0 0 Vertical mound, not overturned 0.3 1.5 0.3 1.5 1.4 6.9 no mound 1.2 6.0 1.3 6.5 3.0 15.0 Unacceptable 3.6 18.0 4.1 20.5 11.1 55.7 Total 20.0 100.0 20.0 100.0 20.0 100.0 Averages and percentages are calculated from original data and therefore there may be discrepancies because of rounding. * Poor performance on this site was due in part to failure of the hydraulic braking on the ripper. Table B .3- D i s t r i b u t i o n o f mound c l a s s e s - Bracke Mounder (from Hedin 198?). Fort St. John Oawson Creek _ _ _ Mackenzie Mound class Avg no. Avg no. % ol Avg no. • A of per total per total por totnl transect transect transect Greater than or equal 0.1 0.5 0.1 0.5 0 0 to 20 cm mineral soil in cap over inverted organic layer 14-19 cm mineral soil 0.2 0.9 2.3 11.5 0.7 3.6 in cap over inverted organic layer 10-13 cm mineral soil 1.0 5.0 5.8 29.0 2.9 14.6 in cap over inverted organic layer 6-9 cm mineral soil 5.1 25.5 5.9 29.5 3.8 19.1 in cap over inverted organic layer 3-5 cm mineral soil 6.2 30.9 1.8 9.0 4.9 24.5 in cap over inverted organic layer Greater than or equal 1.7 8.6 0 0 1.7 8.6 to 5 cm well-decomposed invened organic layer over undisturbed organic Acceptable 14.3 71.4 159 79.5 14.0 704 Less than or equal to 0.2 0.9 0.4 2.0 0.3 1.4 2 cm mineral soil in cap over inverted organic layer Less than 5 cm well- 0 0 0.1 0.5 0 0 decomposed inverted organic layer over undisturbed organic Inverted organic mound 2.3 11.8 0.1 0.5 2.1 10.5 Organic mound, not 1.5 7.7 0.6 3.0 1.2 5.9 inverted Mineral over undisturbed 0.3 1.4 1.7 8.5 0.2 0.9 organic Vertical mound, not 0 0 0.1 0.5 0.1 0.4 overturned No mound 1.4 6.8 1.1 5.5 2.1 10.5 Unacceptable 5.7 28.6 4.1 20.5 6.0 29.6 Total 20.0 100.0 20.0 100.0 20.0 100.0 Averages and percentages are calculated from original data and therefore there may be discrepencies because of rounding: Table B.4. Comparison of moundeing success (from Hedin 198?). Overall success acceptable and Success In achieving deep unacceptable mound classes mineral capping - i 10 cm BY MACHINE INCREASING SUCCESS-. Sinkkila Mackenzie Dawson Creek Fort St. John MINISTRY mounder Fort St. John Vanderhool Mackenzie Dawson Creek Bracke mounder Fort St, John Mackenzie Dawson Creek INCREASING SUCCESS-. Sinkkila Mackenzie Fori St. John Dawson Creek MINISTRY mounder Fort Si. John Vanderhool Mackenzie Dawson Creek Bracke mounder Fort St. John Mackenzie Dawson Creek INCREASING SUCCESS-. 1. FORT ST. JOHN Bracke mounder Ministry mounder Sinkkila 2 DAWSON CREEK Sinkkila Bracke mounder Minislry mounder 3. MACKENZIE Sinkkila Bracke mounder Ministry mounder BY SITE INCREASING SUCCESS-. 1. FORT ST. JOHN Bracke mounder Sinkkila Ministry mounder 2. DAWSON CREEK Bracke mounder Sinkkila Ministry mounder 3. MACKENZIE Sinkkila Bracke mounder Ministry mounder Machines or locations underlined with the same line are not statistically different to 9 5 % confidence. Table B .5 . Average dimensions of acceptable mounds - M i n i s t r y Mounder a (from Hedin 1987). Mound class Fori SI. John Height Area cm cm 2 Dawson Creek Height cm Area cm 2 Mackenzie Vanderhool Height Area Height Area cm cm 2 cm cm 2 Greater than or equal to 20 cm mineral soil in cap over inverted organic layer 14-19 cm mineral soil in cap over inverted organic layer 10-13 cm mineral soil in cap over inverted organic layer 6-9 cm mineral soil in cap over inverted organic layer 3-5 cm mineral soil in cap over inverted organic layer Greater than or equal to 5 cm well-decomposed inverted organic layer over undisturbed organic 37 29 22 1552 950 38 4017 21 37 1564 35 3863 33 1209 34 3692 36 2033 31 31 2614 35 2833 1829 2389 25 2076 2063 25 2113 1018 27 2594 2150 28 1567 Overall 1328 36 3882 35 2397 27 2094 • Dimensions shown only when sample size was greater than 5. Table B.6. Average mound dimensions o f acceptable mounds - S i n k k i l a 3 , (from Hedin 1987). Mound class Fori Si. John Height cm Area cm* Dawson Creek Height Area cm cm2 Mackenzie Height Area cm cm2 Greater than or equal to 20 cm mineral soil in cap over inverted organic layer 14-19 cm mineral soil in cap over inveried organic layer 10-13 cm mineral soil in cap over inverted organic layer 6-9 cm mineral soil in cap over inverted organic layer 3-5 cm mineral soil in cap over inverted organic layer Greater than or equal to 5 cm well-decomposed inverted organic layer over undisturbed organic 32 31 28 3050 1856 1650 1496 31 30 2067 2549 2295 2048 1428 31 29 28 34 2215 1619 1263 2178 Overall 31 1626 2199 32 1872 Dimensions shown only when sample size was greater than 5. Table B . 7 . Average mound dimensions of acceptable mounds - Bracke Mounder 3 , (from Hedin 1987). Fort St. John Dawson Creek Mackenzie Mound class H e | g h | A r e a H e i g n l A r e a H e i g n , A r e a cm cm 2 cm cm 2 cm cm 2 Greater than or equal to 20 cm mineral soil in cap over inverted organic layer 14-19 cm mineral soil 26 1474 24 1500 in cap over inverted organic layer 10-13 cm mineral soil 24 936 23 1912 24 1241 in cap over inverted organic layer 6-9 cm mineral soil 21 889 20 1660 22 1339 in cap over inverted organic layer 3-5 cm mineral soil 19 913 18 1824 21 1137 in cap over inverted organic layer Greater than or equal 16 758 24 1328 to 5 cm well-decomposed inverted organic layer over undisturbed organic Overall 20 890 22 1745 23 1257 * Dimensions shown only when sample size was greater than 5. Table B.8. Ground contact within acceptable mound classes (from Hedin 1987). Fort St. John Dawson Creek Mackenzie Vanderhool (no.) (no.) (no.) (no.) Sinkkila Good ground contact 164 152 163 N/A Poor ground contact 0 6 13 Total 164 Tse 176 Ministry mounder Good ground contact ' 158 180 183 181 Poor ground contact 0 6 3 2 Total 158 186 186 183 8racke mounder Good ground contact 156 154 150 N/A Poor ground contact 1 4 5 Total 157 158 155 Appendix C Results of the environmental monitoring project (FRDA 1.25) Graphs prepared by S. Jenvey under contract to MOF. MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Iron Creek, 1987 j i i n | i i i i f T r i i 'i i 'I'T i r i 1 " ! 1 r | i i i i | r f r r p i i i i | i i i i | i i i i r i T T i | i i i i | i f i i | i i i T | i T 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Iron Creek. 1987 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Iron Croak. 1987 ' [ " I ' I ' I ' I ' I i i i I'I'S'I'I'I'I'-I i i i ) i i i i | I ' I ' I i | i i i i | i • i i | i I i i | 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day MECHANICAL SITE PREPARATION STUDY F.R.DJV. 1.25: Iron Crack. 1987 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum 118 MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.2S: Iron Creak. 1987 —8 I i i i i 11 i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i • • | 1 1 ' i | ' i i i | • • ' • | • i 1 1 1 1 I ' 1 1 1 I ' ' 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Iron Crook. 1987 26 - i _ 24 -22 -2 20 -\ x 18 --2 --4 --6 f i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum E o o • u c 3 0 J l O E a o a E o » MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Iron Creak. 1987 119 26 24 -22 -20 -18 -16 -14 -12 -10 -8 -6 -4 -2 #• -0 -2 --4 --6 I I I I | I I I I | 1 I I I | I I I I | T - l I I | I I I I | I I 1 I | I I I I | I I I I | I I I I | I 1 I I | I • I I | I I I I | I I I I | I 220 225 230 235 240 245 250 255 260 269 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.DJk. 1.25: Iron Craek, 1987 26 - i 24 -22 --4 -—6 — i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i • | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Iron Crook, 1987 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Iron Crook. 1987 1 1 1 1 1 1 1 i 11 i 1 1 I 1 1 i 1 1 1 i i i I i 1 1 1 1 1 1 1 1 I i i i i l 1 1 i 11 1 1 1 i I 1 1 1 1 1 1 1 1 11 i 1 1 1 I » 1 1 i l i 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Stewart Lake, 1987 40 -| • 35 -30 -25 -0 j i i i i | i i i i | i i i i | i i i • | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day MECHANICAL SITE PREPARATION STUDY F.R.DJ,. 1.25: Stewart Lake, 1987 30 - i 1 20 -10 -0 -10 --20 -—30 1 " i - i r [ f i i r y i i i i | i i T"i | r T i i ]• i i r i | i i r T [ i i i r f i T T ' I \ n i r \ i i i i j r i i r \ i n i r; i i r i \ i i 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Stewart Lake. 1987 26 - i —6 - j " i I I i | i i i v\ T i r i j i T r i | i i i i | r i i i ] i f i r j r i i i | i i i i | I ' m ] i r r i \ i i i i | i i i r \ 11 i i | 1 1 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.DJV. 1.25: Stewart Lake, 1987 26 -24 -22 -20 -18 -16 -14 -12 -10 -8 -6 -4 -2 -0 --2 --4 --6 - ''' • 1 1 ' ' 1 1' ' 1 ' 1' 1 ' 1 1 1 ' 1 ' 1 '' 1 ' 1 '' '' 1 ' ' • • 1' • • ' 1 1 1 1 I 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I • • • • I • • • •• I • • i • I • • • • | • I I I 1 T rT ' | ••• • ) I • • I | I I I I | I I I I | I I I I | | | | | | | | | | | | | | | | | 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Stewart Lake. 1987 11 i i i 11 i i i 11 i i i I i i i i 11 i i i I i i i i I i i 1 1 I i i i i I 1 1 i 1 1 1 1 i i I i i i i I i i i i I i i i i I i i i i I i i 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.DA. 1.25: Stewart Lake. 1987 | i 1 1 i 1 1 i i i 11 i 1 1 11 i i i i i • i • i 1 1 1 1 i 1 1 i i 1 1 1 1 1 [ 1 1 i 11 1 1 i 11 1 1 1 1 1 i 1 1 1 1 r 1 1 i 11 i 11 11 i 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum 124 MECHANICAL SITE PREPARATION STUDY F.R.DJk. 1.25: Stewart Lake. 1987 220 I i i i i I i i 1 1 I i i i i I i i i i I i i i i I 1 1 i i I i i i i I i i i i I i i i i I i i i i I i i i i I i i i i I i i i i 11 i 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.DJL 1.25: Stewart Lake. 1987 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day — Maximum + Minimum 125 MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Stewart Lake. 1987 26 - i 24 -22-1 - 4 H —6 I i i i i | i i i i | i i i 1 1 i i 1 1 | i i i i | i i 1 1 | 1 1 i i 1 1 1 i i 1 1 1 i i | 1 1 i i | i i i i | i i i i | i i i i | i i i i | 1 1 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MACKENZIE CLIMATE STATION Summer, 1987 40 - r 35 H Si 30 -o a \ M E 25-^ 0 I i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i 11 | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day MACKENZIE CLIMATE STATION Summer. 1987 30 - i -20 -—30 | i < ' i | i i i i | i i i i | i i i i | i i | i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i i i | i i 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.DJL 1.25: Mackenzie Site. 1987 26 -| 24 -22 -20 -18 -16 -2 -0 -2 --4 -—6 — i i i i | i i i i | i i i i | i i i i | i i i i | i 1 1 i | i i i i | i i i i 11 i i i | i i i i | i i i i | i i i • | i i i • | i • i i | i i 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MACKENZIE CLIMATE STATION Summer, 1987 ' | I T I ' I ' I I ' l T I I ' l ' l ' l ' l I I I ' l ' l I I I I I I I I [ I I I I I I ' l ' l I I I I I I I I I I I I I I I I I ' I ' I ' I I I I I I I I I l - l ' 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Mackenzie Site. 1987 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Minimum Julian Day Maximum + MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Mackenzie Stte. 1987 i i i i 11 i i i l i i 11 11 1 1 1 l 11 i i l i i i i l 11 11 l i i i 11 1 1 1 11 i i i i l i i i 11 i i i i I 1 1 1 111 i i i l 11 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day — — Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.DJL, 1.25: Mackenzie Stte, 1987 -- i r n - i T T r r p i r r r r t i r | - r r i T | 1 1 1 r\ i t i i | i i i i [ i i n - | r r r i \ i i i t | i i i i [ i i i i - f i r i i - y r i — 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.DJV. 1.25: Mackenzie Site. 1987 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Jultari Day Maximum + Minimum MECHANICAL SITE PREPARATION STUDY F.R.DJV. 1.25: Mackenzie Site. 1987 Julian Day Maximum + Minimum 130 MECHANICAL SITE PREPARATION STUDY F.R.D.A. 1.25: Mackenzie Site, 1987 26 - i . — : . 24 -22 -20 -2 1 8 H I ' ' • ' I " " " ' I ' ' " R 1 1 ' | 1 1 1 1 | ' ' ' ' | ' ' | I I I I | I I I I | I I I I | I I I I | I I I I | | | | | | | | | | [ | 220 225 230 235 240 245 250 255 260 265 270 275 280 285 290 Julian Day Maximum + Minimum 

Cite

Citation Scheme:

        

Citations by CSL (citeproc-js)

Usage Statistics

Share

Embed

Customize your widget with the following options, then copy and paste the code below into the HTML of your page to embed this item in your website.
                        
                            <div id="ubcOpenCollectionsWidgetDisplay">
                            <script id="ubcOpenCollectionsWidget"
                            src="{[{embed.src}]}"
                            data-item="{[{embed.item}]}"
                            data-collection="{[{embed.collection}]}"
                            data-metadata="{[{embed.showMetadata}]}"
                            data-width="{[{embed.width}]}"
                            async >
                            </script>
                            </div>
                        
                    
IIIF logo Our image viewer uses the IIIF 2.0 standard. To load this item in other compatible viewers, use this url:
http://iiif.library.ubc.ca/presentation/dsp.831.1-0097403/manifest

Comment

Related Items