The following Participating Institutions are custodians for this species in the CPC National Collection:
Rae Selling Berry Seed Bank & Plant Conservation Programs
The conservation of Delphinium leucophaeum is fully sponsored.
Greene contributed to this Plant Profile.
Delphinium is a large, circumboreal genus of herbaceous perennial taxa many of which are widely distributed. The vast majority of species have blue, bumblebee pollinated flowers. Ken Chambers, a dean of Oregon botany, noted a surprising coincidence in there being three rare larkspurs in the Willamette Valley of Oregon: Delphinium oreganum, D. pavonaceum (also a CPC NC species), and D. leucophaeum. He hypothesized that their origins might be connected with global climate change. Not in so many words, and not referring to the current one, but that of the end of the Ice Age, which saw a series of truly massive floods that inundated the Willamette Valley between 15,000 and 12,800 years ago. They are a fascinating tale in and of themselves (Google Missoula Floods), but thats another story. Suffice it to say they were large enough to bring large granite boulders all the way from Montana to Oregon, leaving in their wake lots of newly denuded land.
Delphinium leucophaeum is endemic to the northern end of the Willamette Valley, in and around Portland, OR, with one population known from just across the Columbia River, in Washington. D, oreganum and D. pavonaceum are found a bit further south mostly east and west of the Willamette River, respectively.
Both the common and scientific names of pale larkspur, Delphinium leucophaeum refer to the flower color, which is a brilliant white except for the tips of the two upper, nectariferous petals in the center of the flower, which are blue.
Distribution & Occurrence
Upland prairies often on shallow soil, and rocky basaltic cliffs along the lower Willamette River watershed.
|Twenty four element occurrences are known, 23 of which are in Oregon, and one in adjacent Washington.
Currently, four of the Oregon populations are known only from herbarium specimens dating from the late 19th or early 20th centuries. The mean population size is ca. 677 individuals, median population size is 27 individuals, and only four exceed the mean value, ranging in size from 1000 to 5,000. Eight have fewer than 100 individuals.
Conservation, Ecology & Research
Small population sizes
Hybridization with congeners threaten genetic integrity.
The Berry Botanic Garden (now RSBSB&PCP) has conducted germination and propagation studies, and in the early phases of a combined translocation / reintroduction project.
The Rae Selling Berry Seed Bank has over 50,000 seeds in 180 separate accessions from possibly as many as 16 sites covering both Oregon and Washington.
Better protect roadside populations from mechanical damage and exposure to herbicides.