Garry Oaks Declining in Endangered Ecosystem
The relatively undisturbed example of endangered Garry oak savanna at Rocky Point near Victoria, BC seems to be a fleeting artefact of European settlement.
While the oldest oak tree there is now 300 years, most of the oaks sprouted after 1850 when native peoples left and European farmers moved in.
Previously written accounts describe the site on the southern tip of Vancouver Island as open prairie with only a few scattered oak trees. Indigenous peoples likely maintained this grassland ecosystem with regular burning. There is no evidence of fire since.
Around 1950, the oak ecosystem shifted again with an influx of coniferous trees, primarily Douglas-fir. Garry oak seedlings are still plentiful beyond the shade of conifers. But not enough oak saplings survive to maintain the mature oak population.
It is unclear why conifers are now crowding out the Garry oaks. Lack of fire, deer browsing, and exotic grasses and shrubs could all be contributing. Using prescribed burning to restore the ecosystem is fraught with problems, including the Department of National Defence's stockpile of ammunition stored nearby.
Ze'ev Gedalof, Marlow Pellatt and Dan J. Smith. 2006. From Prairie to Forest: Three Centuries of Environmental Change at Rocky Point, Vancouver Island, British Columbia. Northwest Science. 80(1): 34-46.