UBC Theses and Dissertations
A cyto-taxonomic revision of the genus Rosa in the Pacific North-West Lewis, Walter Hepworth
The delimitation and taxonomic study of Rosa species in the Pacific North-west was approached by utilizing several experimental methods. Randomly sampled mass collections analyzed statistically and grouped into climatic regions was the most important method and it served as the basis for all conclusions. To corroborate these results, ‘ordinary' herbarium material, transplants, progeny testings, and cytological examination of chromosome and cell sizes were examined for each species. From the results, the populations were divided into four species, four subspecies, one hybrid, and one form. They have been named: Rosa acicularis Lindl., R. arkansana Porter, R. pisocarpa Gray, R. Woodsii Lindl., R. gymnocarpa Nutt. ssp. gymnocarpa, R. gymnocarpa Nutt. ssp. apiculata (Greene) Lewis ined., R. nutkana Presl. ssp. nutkana, R. nutkar ssp. Spaldingii (Crep.) Lewis ined., R. acicularis Lindl. X R. nutkana Presl, and R. nutkana Presl f. muriculata (Greene) Lewis ined.