UBC Undergraduate Research

A pilot study of increment cores from young defoliated western hemlock on Haida Gwaii Nethercut-Wells, Acacia


Increment cores from five stands on Haida Gwaii, British Columbia were measured to identify radial growth suppressions caused by western blackheaded budworm (Acleris gloverana) defoliation. Z-scores were calculated based on annual basal area to identify periods of suppression and to quantify the severity of the suppression. Comparisons between stands illustrated an association between certain stand characteristics (density and age) and indicators of defoliation severity (percent mortality of western hemlock, suppressions per tree, and length of time suppression lasted). Although this pilot study was not able to make conclusions about growth suppressions and their relation to defoliation, it played an integral role in the development of further studies that will be able to achieve this.

Item Citations and Data


Attribution-NonCommercial-NoDerivatives 4.0 International