Today’s entry is written by Bryant. The first photograph is from Charles Thirkill, a resident of Nanaimo who has been prominent in preserving this rare species at this location in British Columbia, and the second image is from Bryant. He writes:
Last Thursday, I was fortunate enough to tag along with Daniel Mosquin and Tony Maniezzo, the curator of the North American Gardens (including the Garry Oak Meadow and Woodland Garden, on their scouting trip to various Garry oak ecosystem sites on Vancouver Island. The main purpose of the trip was to examine different Garry oak landscapes and compare the plants and plant assemblages that are growing in the UBC Botanical Garden with their counterparts in the wild. A secondary purpose was to locate and observe rare plant species, in the hope that the Garden will one day participate in conservation programs for these species.
This photo shows Lotus pinnatus (bog birds-foot trefoil), a member of the Fabaceae, at one of its few locations on Vancouver Island. It is a short-lived perennial that grows from a thick taproot, and can be observed in flower from May to June. It has alternate compound leaves, each with 2-4 pairs of oppositely-arranged leaflets and a terminal leaflet. It is found in moist depressions in shallow soil on exposed coastal lowlands. In Canada, it grows in Garry Oak habitat on southeast Vancouver Island and Gabriola Island.
Elsewhere, Lotus pinnatus is native to California, Oregon, Washington and Idaho. The species is not considered threatened globally; however, it is considered extremely rare in Canada (the northern extent of its distribution). In Canada, it is limited to 5 recorded sites, with 83% of its Canadian population residing on the Harewood Plains in Nanaimo, British Columbia. This highly limited Canadian distribution has earned this species an N1 (nationally endangered) ranking by the Committee on the Status of Endangered Wildlife in Canada. Provincially, it is ranked as an S1 (red-listed/critically imperiled) status in B.C., the highest threatened level that can be applied to a species.
Since Lotus pinnatus usually grows in association with water seepage sites, any activity that could cause drainage through soil compaction, channeling or other methods could cause local extirpations of this species. The biggest threats to the British Columbia populations of this species come from logging, unauthorized 4×4, ATV and dirtbike use, development, and encroachment of invasive species. The site where the pictured specimen was found was not marked in any way and showed recent tracks and disturbance from unauthorized recreational vehicles.
Only 7% of the plants in Canada reside under some official protection, those that are in the Woodley Range Ecological Reserve. The percentage of protected habitat for Lotus pinnatus is small because the majority of the Canadian populations exist on private land. Landowners have made efforts to keep off-road recreationists out of the fragile habitat by placing gates, cement barriers and ditches at potential entrance sites, but to little avail. On the bright side, there are steps being taken to help Lotus pinnatus recover. In 2006, the “Recovery Strategy for Multi-Species at Risk in Vernal Pools and Other Ephemeral Wet Areas Associated with Garry Oak Ecosystems in Canada” was developed for Lotus pinnatus, and five other local species, under the Species at Risk Act (SARA). This recovery strategy is a major step in the protection of the mentioned species; the next step requires a proposed action plan, which is currently in the process of development, to delineate site-specific management goals and objectives.
In other news, Lotus pinnatus was named the floral emblem of Nanaimo in 2010 with the hopes to raise public awareness about its conservation status. For information on the local recovery efforts for this species contact the Garry Oak Ecosystems Recovery Team.