Distribution: Occurring east of the Cascades crest, where endemic to Kittitas County.
Habitat: Open, vernally wet, gently sloping meadows of fine-textured clay soils at approximately 1200 meters.
Flowers: May-June
Origin: Native
Growth Duration: Perennial
Conservation Status: Threatened in Washington (WANHP)
Pollination: Bees, flies, butterflies, beetles, wasps
Glabrous perennial from a taproot, 0.8-3.4 dm. tall; root 2-28 cm long, with a slight tuberous swelling 0.5-2 cm long that narrows to a simple taproot.
Ttypically 3, basal, 9-18 cm long and 4-17 cm wide, ternately or ternate-pinnately 2-several times divided into narrow ultimate segments 3-27 mm long and 0.2-2.3 mm wide.
Inflorescence a compound umbel, the rays typically unequal, flowers yellow, 1-28 mm long; involucel bracts narrow to linear, bract number 0u201314 with typically values of 5 to 7. Bracts are 1.5u20136.4 mm in length, 0.1u20130.8 mm in width, free to base, often with a well-developed mid-vein, occasionally inserted on flower pedicels.; pedicels 0.7-2.6 mm. long.
Glabrous, elliptic, 4.0-7.8 mm long and about 6 mm wide, quite flat; the wings 0.2-0.5 mm wide.
PNW Herbaria: Specimen records of Lomatium knokei in the Consortium of Pacific Northwest Herbaria database
WA Flora Checklist: Lomatium knokei checklist entry
OregonFlora: Lomatium knokei information
E-Flora BC: Lomatium knokei atlas page
CalPhotos: Lomatium knokei photos