Die Dreharbeiten fanden unter anderem im Naturschutzgebiet Garry Oak auf Vancouver Island statt
English: Title: The Canadian field-naturalist Identifier: canadianfieldnat118otta (find matches) Year: 1919 (1910s) Authors: Ottawa Field-Naturalists' Club Subjects: Publisher: Ottawa, Ottawa Field-Naturalists' Club Contributing Library: Harvard University, Museum of Comparative Zoology, Ernst Mayr Library Digitizing Sponsor: Harvard University, Museum of Comparative Zoology, Ernst Mayr Library View Book Page: Book Viewer About This Book: Catalog Entry View All Images: All Images From Book Click here to view book online to see this illustration in context in a browseable online version of this book. Text Appearing Before Image: 2004 Douglas and Penny: Howell's Triteleia in Canada 177 Text Appearing After Image: Figure 3. Habitat of Triteleia howeUii in a Que reus garryana stand in the Cowichan Garry Oak Preserve near Quamichan Lake. Dactylis glomerata is tiie dominant grass in this late summer photo. The suppression of fire within the past century may also have contributed to the decrease of Triteleia how- eUii populations. Most of the sites in which T. howellii has been collected were likely maintained in the past as a result of periodic fires, both natural and unnatural. In the past, aboriginal peoples probably set fire to these stands to maintain them as an important habitat for wildhfe (Roemer 1972). Since that time, these sites have experienced little disturbance, resulting in the in- vasion and expansion of many other species, especial- ly introducted grasses. The introduction of European species has resulted in substantial, and probably irreversible, changes not only to the grass-dominated meadows associated with Quercus garryana, but also to the rocky xeric sites north and west of Victoria where Triteleia howellii has been collected in the past. One of the most devas- tating species is Scotch Broom (Cytisus scoparius), which has become a dominant shrub on xeric, exposed sites throughout much of southeastern Vancouver Island and the Gulf Islands. Much of the vegetation is now dominated by introduced grasses. These species include Early Hairgrass (Aira praecox), Sweet Vernal- grass (Anthoxanthum odoratum), Cynosurus echinatus and Dactylis glomerata. Some of the populations contain very few plants. Once a population becomes small, it becomes more vulnerable to demographic and environmental vari- ation and loss of genetic variability. In some cases, small populations are at risk of inbreeding depression, genetic drift and loss of fitness (Primack 1998). The population with the best protection is located at the Cowichan Garry Oak Preserve where the general public is excluded. This five-hectare stand near Quami- chan Lake on Vancouver Island represents the best example of a Quercus garryana woodland in the prov- ince and probably one of the best in the Pacific North- west. The stand contains a relatively low number of exotic species and has active management plans in place. This site also contains the largest known popu- lation of T. howellii in the province (Douglas et al. 2002*). A number of Triteleia howellii populations are also in small regional parks in the Greater Victoria area. These include populations at Beacon Hill, Witty's Lagoon, Thetis Lake, and Horth Hill. Most of these parks receive little active management at the present time, at least with respect to their rare plants. Park enhancement projects, road and trail developments and heavy recreational use by humans often result in the destruction of the native vegetation and rare plant species. Triteleia howellii could be a candidate species for protection under the provincial Wildlife Amendment Note About Images Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original work.