Synonyms: Lupinus sulphureus ssp. kincaidii, Lupinus sulphureus var. kincaidii, Lupinus oreganus var. kincaidii, Oregon lupine
The genus Lupinus poses many taxonomic challenges due to the extremely variable nature of the species and intergradations between recognized taxa, a situation that in many instances is likely the result of or complicated by free interbreeding that has obscured species boundaries. Hybridization is known to occur between Kincaid’s lupine and Lupinus arbustus.
Kincaid’s lupine is a perennial arising from a branched crown, usually with numerous unbranched stems (30) 40-80 (100) cm tall, with whitish or brownish stiff to silky pubescence. Basal leaves are usually persistent until after flowering, with petioles (2) 3-5 times the length of the blades; upper cauline leaves have petioles sometimes shorter than the blades. Leaflets typically number 7-12, are narrowly oblanceolate, usually somewhat acute, 2.5-5 cm long, often remaining somewhat folded, and usually glabrous above and sparsely to copiously hairy beneath. Inflorescences are slender, the flowers numerous and arranged in interrupted whorls. Flowers are fragrant and range in color from bluish or purple to yellowish or creamy white, quickly turning orange-brown with age. The banner is distinctively ruffled (markedly concave on the lateral faces), glabrous, and only somewhat reflexed from the glabrous keel. Pods are 3-4 cm long, with 1-6 pinkish-brown to black seeds.
Several other perennial species of Lupinus overlap in range with Kincaid’s lupine: L. arbustus, L. polyphyllus, L. albicaulis, L. albifrons, L. lepidus, L. latifolius, and L. rivularis. Lupinus arbustus is distinguished by its distinctly spurred calyx (versus calyx not spurred) and flowers with banners that are hairy on the back (versus glabrous) and distally ciliate keels (versus glabrous keels), L. polyphyllus has larger leaflets 5-10 cm long (versus 2.5-5 cm), L. albicaulis has leaves with copiously pubescent upper surfaces (versus usually glabrous) and flower banners that lack a distinct ruffle (versus distinctly ruffled), L. albifrons has flower banners that are densely pubescent on the back and well reflexed from ciliate keels (versus banners glabrous on the back and only somewhat reflexed from glabrous keels), L. lepidus plants are shorter (usually 10-35 cm tall versus usually taller than 40 cm) and its flowers have ciliate keels (versus glabrous), and L. latifolius and L. rivularis both have branched stems (versus usually unbranched stems) and flowers with banners fairly well reflexed from ciliate keels (versus only somewhat reflexed from glabrous keels). Hybrids between Kincaid’s lupine and L. arbustus have been documented and may exhibit a spurred calyx.
When to survey
Surveys should be completed when the species is flowering, typically from mid April through June.
Kincaid’s lupine is found in upland prairie remnants and ecotones between grassland and forest. It usually occurs in heavy, well-drained soils at elevations below 838 m (2750 ft).
Commonly associated native plant species include: Agoseris grandiflora, Arbutus menziesii, Balsamorhiza deltoidea, Brodiaea coronaria, Bromus carinatus, Calochortus tolmiei, Cryptantha intermedia, Danthonia californica, Delphinium menziesii, Elymus glaucus, Eriophyllum lanatum, Festuca idahoensis, F. roemeri, Fragaria vesca, F. virginiana, Holodiscus discolor, Iris tenax, Lomatium triternatum, L. utriculatum, Luzula comosa, Madia gracilis, Potentilla gracilis, Pseudotsuga menziesii, Pteridium aquilinum, Sanicula crassicaulis, Silene hookeri, Symphoricarpos mollis, Toxicodendron diversilobum, and Whipplea modesta. Commonly associated invasive plants include Arrhenatherum elatius, Brachypodium sylvaticum, Dactylis glomerata, Festuca arundinacea, Rubus armeniacus, and Cytisus scoparius.
Kincaid’s lupine occurs west of the Cascade Range from Douglas County, Oregon north to Lewis County, Washington, with the majority of populations located in the Willamette Valley. There are historic records of the species from Oak Bay, Victoria, British Columbia, but the last collection from this area was made in 1929, and the species is now considered extirpated in Canada. Kincaid’s lupine occupies the Klamath Mountains, West Cascade Range and Crest, and Willamette Valley ecoregions.
Benton, Douglas, Lane, Linn, Marion, Polk, Washington, Yamhill
Major threats to Kincaid’s lupine include habitat loss due to urbanization, agriculture, forestry practices, and roadside maintenance; competition from non-native plants; and successional encroachment by woody plants due to changes in historic disturbance regimes. Hybridization between Kincaid’s lupine and other co-occurring lupine species may lead to increased resource competition and genetic swamping of the rare parent genes. Crosses between Kincaid’s lupine and Lupinus arbustus have been documented at one site. Other factors that may negatively impact Kincaid’s lupine include seed, fruit, and flower predation by insects and inbreeding depression due to habitat fragmentation and small population sizes.
A U.S. Fish and Wildlife Service 5-Year Review
(pdf document, 584 kB) for Kincaid’s lupine summarizing conservation issues was released in 2010.
Kincaid’s lupine is the primary larval host plant of the federally endangered Fender’s blue butterfly (Icaricia icarioides fenderi) and recovery efforts for these species should be coordinated. Kincaid’s lupine may benefit from additional regulations associated with conservation of the butterfly at sites where the species co-occur.
Did you know?
Kincaid’s lupine reproduces both by seed and by vegetative spread through rhizome growth. Individual clones can live for several hundred years and become very large. Excavations and morphology indicate that a clone can exceed 10 meters (33 feet) across, and plants 10 meters (33 feet) or more apart can be connected by subterranean stems. This complicates population monitoring, as it is difficult to distinguish genetically distinct individuals. Because of this, current monitoring best practices recommend counting square meters of Kincaid’s lupine coverage, rather than individual plants.
Current/Recent ODA projects
Developing population density estimates for nine rare Willamette Valley prairie species (pdf, 5.33 MB)
Currin, R., M. Carr, and R. Meinke. 2008. Developing population density estimates for nine rare Willamette Valley prairie species. Report prepared for U.S. Fish and Wildlife Service, Region 1, Portland, Oregon. Oregon Department of Agriculture, Salem, Oregon.
Hitchcock, C. L., A. Cronquist, M. Ownbey, and J. W. Thompson. 1961. Vascular plants of the Pacific Northwest. Part 3: Saxifragaceae to Ericaceae. University of Washington Press, Seattle.
ORBIC (Oregon Biodiversity Information Center). 2010a. Rare, threatened and endangered species of Oregon. Institute for Natural Resources, Portland State University, Portland, Oregon.
ORBIC (Oregon Biodiversity Information Center). 2010b. ORBIC element occurrence database. Portland, Oregon.
Pendergrass, K. 2010. Introduction to Kincaid’s lupine, a federally-listed threatened plant, and a photo key to the lupines that occur within its range. U.S. Department of Agriculture Natural Resources Conservation Service Technical Notes, Plant Materials No. 40 – Supplement D. Available at http://www.plant-materials.nrcs.usda.gov/pubs/orpmstn9821.pdf
(pdf document, 4.62 MB). Accessed July 21, 2011.
USFWS (U.S. Fish and Wildlife Service). 2000. Endangered status for Erigeron decumbens
(Willamette daisy) and Fender's blue butterfly (Icaricia icarioides fenderi
) and Threatened status for Lupinus sulphureus
(Kincaid's lupine). Federal Register 65:3875-3890. Available at http://ecos.fws.gov/docs/federal_register/fr3502.pdf
(pdf document, 192 kB). Accessed September 19, 2010.
USFWS (U.S. Fish and Wildlife Service). 2006. Designation of critical habitat of the Fender’s blue butterfly (Icaricia icarioides fenderi
), Lupinus sulphureus
(Kincaid’s lupine), and Erigeron decumbens
(Willamette daisy); Final Rule. Federal Register 71:63861-63910. Available at http://www.fws.gov/oregonfwo/Species/PrairieSpecies/Documents/FR2006Oct31WVCHFinal.pdf
(pdf document, 2.60 MB). Accessed September 19, 2010.
USFWS (U.S. Fish and Wildlife Service). 2010a. Recovery Plan for the prairie species of western Oregon and southwestern Washington. U.S. Fish and Wildlife Service, Portland,
USFWS (U.S. Fish and Wildlife Service). 2010b. Kincaid’s lupine (Lupinus sulphureus
[syns. Lupinus oreganus
, Lupinus oreganus
]) 5-year review. U.S. Fish and Wildlife Service, Portland, Oregon. Available at http://ecos.fws.gov/docs/five_year_review/doc3355.pdf
(pdf document, 584 kB). Accessed July 19, 2011.
Wilson, M. V., T. Erhart, P. C. Hammond, T. N. Kaye, K. Kuykendall, A. Liston, A. F. Robinson, Jr., C. B. Schultz, and P. M. Severns. 2003. Biology of Kincaid’s lupine (Lupinus sulphureus ssp. kincaidii [Smith] Phillips), a threatened species of western Oregon native prairies. Natural Areas Journal 23:72-83.