Garry oak meadows were once common throughout southeastern Vancouver Island. They take the form of open stands of stately gnarled oak trees, often carpeted with billowing drifts of wildflowers that bloom in the spring. This "natural parkland" enthralled European colonists, and in part led Sir James Douglas to choose Victoria Harbour as the location of the Hudson’s Bay Co. fort in 1843. What the Europeans may not have understood is that many of these meadows were not altogether "natural." Rather, the Vancouver Island Coast Salish people deliberately managed the land and periodically used prescribed burning to keep the meadows clear of underbrush, to cultivate camas. This beautiful blue wildflower grows from bulbs that provided an important food staple rich in carbohydrates. Bulbs were dug in the late summer, and dried for trade or storage. Camas bulbs were typically cooked in large steam pits with a variety of other foods (e.g. shoots, bulbs, shellfish). Local First Nations communities still collect and cook camas for community feasts and celebrations.
Prescribed fire was necessary to prevent the encroachment of shrubs and other large trees, in areas with deep soil. However, in sites with shallow soil, such as among rocky outcroppings, Garry oak meadows can dominate without human assistance. Natural forest fires were also an important part of these ecosystems, as oak trees are resistant to damage by fire and the herbaceous plants quickly re-sprout in burned areas.
What are Garry oak Meadows?
Garry oak meadows are generally fairly open forests dominated by Garry oak trees (Quercus garryana), with an understory composed of shrubs and/or wildflowers and other herbaceous plants. The oak trees themselves may be large (up to 25 metres tall) and scattered, or, particularly in areas with thin soil, more often dense and stunted.
Garry oak meadows are a subcomponent of the Coastal Douglas-fir
(CDF) Ecosystem, as identified by the Biogeoclimatic Ecosystem Classification system for British Columbia. The CDF ecosystem occurs in a narrow strip along the southeastern tip of Vancouver Island, including some of the Gulf Islands and a small portion of the mainland. As a whole, this region lies in the rain shadow of the mountains of Vancouver Island and the Olympic Mountains in Washington, therefore summers are dry, and winters are mild and wet, although not as wet as most other regions on the west coast.
The present global and Canadian range of Garry oak meadows is shown in the diagrams below:
Present distribution of Garry oak ecosystems in British Columbia
Present distribution of Garry oak ecosystems in North America
What lives in Garry oak Meadows?
Garry oak meadows host more plant species than any other terrestrial ecosystem in Canada. The Garry oak trees (Quercus garryana
) may be found interspersed with other trees such as arbutus (Arbutus menziesii
) and Douglas-fir (Pseudotsuga menziesii
). The understory may include shrubs such as snowberry (Symphoricarpus albus) and wild rose (Rosa nutkana), and/or grasses and flowering herbs. Chocolate lily,Fritillaria lanceolata (photo L. Townsend)
Common herbaceous plants include: camas (Camassia quamash
), shooting star (Dodecatheon
spp.), chocolate lily (Fritillaria lanceolata
), White Fawn Lily (Erythronium oregonum
), satin flower (Sisyrinchium douglasii
), nodding onion (Allium cernuum
), brodiaea, western buttercup (Ranunculus occidentalis
), red columbine (Aquilegia formosa
), sea blush (Plectritis congesta
), yellow montane violet (Viola praemorsa
) and deltoid balsamroot (Balsamorhiza deltoidea
More than 100 species of birds inhabit Garry oak meadows, including rare or endangered species such as the Western Bluebird
, Western Meadowlark
and Coastal Vesper Sparrow
. Lewis's Woodpecker, once common in Garry oak meadows, has been extirpated from the west coast, and the Streaked Horned Lark
has probably met the same fate. Other common birds include bushtits, warblers, towhees, nuthatches, owls, swallows, hummingbirds and hawks.
Large mammals such as black-tailed deer and back bear are sometimes found in Garry oak meadows; Roosevelt elk, once a common member of these ecosystems, are now only found in isolated locations on southern Vancouver Island. Small mammals such as mice, shrews and moles also make their homes and feed in Garry oak meadows. In addition, seven species of amphibians, seven reptiles (including the northern alligator lizard and the Sharptailed Snake
, and more than 800 insect and mite species are found here.
Where are Garry Oak Meadows found?
Garry oak meadows were once fairly common on southeastern Vancouver Island, the Gulf Islands and the Fraser Valley, down through to California. In British Columbia today, Garry oak meadows occupy only about 3% of their former area, having been replaced by residential developments, agricultural fields and urban areas. The following two images show the distribution of Garry oak meadows, in 1800 compared to 1997.
Some of these remnant Garry oak meadows have been preserved and restored by stewardship groups and local governments (see links below).
Distribution of Garry oak meadows in Victoria Area (orange shading), circa 1800
Distribution of Garry oak meadows in Victoria area (pink shading), circa 1997
(maps image used with permission from the Province of British Columbia)
What threatens Garry Oak Meadows?
Garry oak meadows are most threatened by development that replaces them with other types of land use such as agriculture, roads, residential housing and urban areas. Unfortunately, existing trees and vegetation are rarely preserved within new developments, despite the fondness people have for these ecosystems. Invasive species
are another major threat. Plants that are introduced, either intentionally or accidentally, from other geographic areas can compete for nutrients and space with native plants, and usually do not offer as valuable wildlife habitat and food. Some of the most common invasive plant species in Garry oak meadows include Scotch broom (Cytisus scoparius
), Himalayan blackberry (Rubus discolor
), and grasses including orchardgrass (Dactylis glomerata
), Kentucky bluegrass (Poa pratensis
), sweet vernalgrass (Anthoxanthum odoratum
) and hedgehog dogtail (Cynosurus echinatus
). English ivy (Hedera helix
) poses a special threat in that it can climb and strangle even mature Garry oak trees. Wildflowers (camas, deltoid balsamroot, sea blush and western buttercup) in a Garry oak meadow
Forest fire suppression has had a major impact on Garry oak ecosystems. Before people began putting out fires, lightning-started fires (as well as fires deliberately set by First Nations) periodically swept through Garry oak meadows, burning off dry grasses, shrubs and young trees less tolerant of fire than Garry Oaks. These fires would have been relatively low in intensity, since they occurred relatively frequently, preventing fuels on the forest floor from accumulating. Therefore, fire resistant Garry oaks would have survived, and herbaceous plants would have vigorously resprouted after the burn. Due to the risk of property damage in populated areas, reintroducing fire into these ecosystems is not always possible. However, in certain cases prescribed fire can be applicable and quite useful in controlling invasive species and re-establishing a natural disturbance regime.
How can I help preserve Garry Oak Meadows?
Visit some of the local Garry oak meadow sites throughout the parks and other natural areas in the region, particularly in the spring when the flowers are blooming. Bring along some plant and animal field guides, a camera and binoculars. Some parks offer interpretive tours, and sometimes Garry oak stewardship groups will offer field trips open to the public.
If you are fortunate enough to have Garry oaks on your property, treasure them! Consider allowing some young acorns to grow into new oaks, and/or start to recreate a Garry oak meadow with native wildflowers. Use native plants
in your garden; many local nurseries now carry native trees, shrubs and flowers adapted to local climate and conditions.
Help to control and remove invasive species
on your property, so they don't escape to the wild and threaten Garry oak and other ecosystems
Additional Information & Links © Top and bottom images courtesy of L. Townsend & Mary Sanseverino