The morphology, phenology and stem demography of devil's club and thimbleberry were examined to elucidate their niche utilization strategies. The study was conducted in the Kitimat River valley in west central B.C. during the 1986 and 1987 growing seasons. Thimbleberry was sampled in a girdled alder site and a nongirdled alder site, whereas devil's club was sampled in an old growth forest. The variation in the plant characters, as summarized by principal components axes, was apportioned within and among clones, between sites, years, and species. Except for the thimbleberry vegetative phenology, within-sites differences accounted for most variation and variation between-sites often exceeded that between years. Moreover, between-species differences accounted for less variation than within-species differences for morphology and phenology. The variation in plant characters was also examined in relation to canopy cover, soils and adjacent vegetation using multivariate methods. The rate of vegetative development for devil's club in 1986 increased as canopy cover decreased; other environmental measures were uncorrelated with devil's club. Both vegetative and reproductive rates of development increased with disturbance due to girdling and increasing moisture for the combined girdled and ungirdled thimbleberry data set. Similarly, morphdodcal size was greater for the combined thimbleberry data set with increasing moisture and dsturbance. Environmental correlations were reflected differently within-sites, however, with rates of development, plant size and the number of flowers decreasing with increasing moisture at the nongirdled thimbleberry site. The relationship between plant characters was also assessed. Phenology and morphology were correlated for both devil's dub and thimbleberry; stem development began earlier and was more rapid with increasing stem size. Demography and phenology were unrelated. Both species displayed different niche utilization strategies; thimbleberry being more flexible than devil's club. In contrast to devil's dub, thimbleberry is morphologically a phenologically responsive to disturbance and is mizomatous rather man stoloniterous. Stems and lateral branches also had several phonological and developmental possibilities. This flexibility imparted an advantage to thimbleberry in the fluctuating conditions of its earlier successional niche. The differing correlation structure between and within thimbleberry sites suggests that several scales of observation are necessary to clarify plant-environment relationships. Moreover, as environmental characters interact differently with plants from site to site, management must be site specific. Alder girdling may be a judicious management technique at drier sites, where thimbleberry is not as prolific under an open canopy. / Science, Faculty of / Botany, Department of / Graduate

This dissertation was undertaken in collaboration with the Nisga’a First Nation of northwestern British Columbia to document their traditional plant knowledge. This information was gathered through collaborative audio recorded open-ended discussion with 21 Nisga’a elders, supplemented with material from the published literature and archival sources. Background information with respect to the Nisga’a culture, language, geography, plant classification and resource management is documented in the past and as exercised today. Nisga’a names or uses of 110 plant species are described. Of these, 72 species were documented as having been used for food, 52 for medicinal purposes; 12 for spiritual purposes and 70 for technological purposes. The role of plants in traditional Nisga’a culture is further explored through comparisons of plant distribution, plant names and pre-contact trade between the Nisga’a and their immediate neighbours, the Gitxsan, Tsimshian, Haida, Tahltan and Tlingit First Nations. Maps are presented which highlight the distribution of seven plant species traditionally important in these cultures: Shepherdia canadensis (soapberry), Vaccinium membranaceum (black huckleberry), Oplopanax horridus (devil’s club), Corylus cornuta (beaked hazelnut), Malus fusca (Pacific crabapple), Veratrum viride (false hellebore), and Taxus brevifolia (western yew). Currently, one of the plants most important to the Nisga’a is wa’ums or devil’s club (Oplopanax horridus). Devil’s club stems were measured in clearcuts of different ages to examine how quickly this important spiritual and medicinal species recovers after logging. Results suggest that although devil’s club does persist after clearcut logging, stems of a suitable size are rarely found in cutblocks less than 10 years old and that time since logging only partially accounts for the persistence or recovery of this species. The dissertation concludes with a discussion of historical Nisga’a plant knowledge. The gender of those who have held and transmitted traditional knowledge and the gender of present knowledge holders is tabulated and discussed. Results suggest that although both men and women hold and pass on traditional knowledge, women were and still are more commonly involved in its transmission to the next generation. Current plant uses are highlighted and prospects for the sustainable use of plants for personal and commercial purposes are discussed. / Graduate