Results and Data from an Ecological Study of Garry Oak (Quercus garryana) Ecosystems in Southwestern British Columbia

This report and CD consist of excerpts from my MSc thesis from 1996, covering the context for the study, results and survey data. In the thesis, I sampled the plant communities associated with Garry oak (Quercus garryana) in British Columbia to develop a classification for use in resource management. An overview is included here of a total of 43 plant communities. Descriptions have also been placed on the Web (Erickson 1998) and, with some modification, are presented in a field guide (Erickson and Meidinger 2007).

A study of Garry oak ecosystems was compelling, given that they had been designated as critically imperiled in British Columbia. I used quantitative methods as well as subjective assessments to assemble a numerically adequate database, apply a landscape approach, and include wide geographic coverage. Although European phytosociology influenced some facets of my study, my classification is much more strongly related to other plant community research in the Pacific Northwest.

I therefore placed the classification in a scientific context through objective comparisons with the level of differentiation from other studies throughout the Pacific Northwest. The 43 plant communities identified and described in the thesis are placed in a setting of scientific work through subjective comparisons with the literature on similar plant communities.

Ecosystem relations of the plant communities are depicted from the collected field data, and supplemented with objective results at a broad level. Ecological hypotheses are suggested, along with management interpretations for each of the plant communities. In my thesis, preservation and active management are emphasized in a management strategy for Garry oak habitat as a whole.