Today’s entry is the first of at least five on narrow-range endemics of British Columbia, Washington and Oregon.
Wenatchee larkspur is found only in central Washington, in an area no larger than 30km long by 10km wide. According to the Center for Plant Conservation (CPC), Delphinium viridescens is a plant of “moist meadows, moist micro-sites in open coniferous forest, springs, seeps, and riparian areas…characterized by surface water or saturated upper soil into early summer, with poorly drained and silty to clayey-loam soil”. This is an excellent description of the conifer-surrounded meadow environment where these photographs were made.
Due in large part to its narrow distribution, it is listed as endangered in Washington state and has been proposed as a candidate for federal endangered or threatened status in the USA. As noted by the CPC in the link above, threats to the roughly ten thousand individual plants include: “habitat loss due to residential development, hydrologic changes from development and road construction, timber harvest and livestock grazing”. Despite low numbers, the species “maintains considerable levels of genetic variation both within and among populations”, according to Richter, ST, et al. 1994. Genetic Variation within and Among Populations of the Narrow Endemic, Delphinium viridescens (Ranunculaceae). Am. J. Bot.. 81(8): 1070-1076.
Delphinium viridescens is a perennial plant typically growing to 1.2m in height, though occasionally to 2m. Photographs of the entire plant are available from the Burke Museum: Delphinium viridescens. The Flora of North America has a scientific description of Delphinium viridescens.