Lomatium triternatum, ternate lomatium

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Intermountain Flora
Perennial, the taproot edible, elongate and seldom much thickened, surmounted by a simple or occasionally few-branched crown or short caudex; stems or scapes solitary or few, more or less erect, mostly (1) 2-8 dm tall at maturity (or up to 12 dm in var. anomalum), finely and often densely spreading-hirtellous, varying to rarely glabrous; leaves chiefly or wholly basal or low-cauline, 1 or more fairly well developed leaves often present on the middle or evn the upper part of the stem, but the stem not appearing very leafy, the leaves ternately to ternate-pinnately (or at the base quinately) 2-3 times (seldom only once) cleft into long, usually narrow segments or leaflets 1-10 (20) cm long (broader and up to 1 or even 2 cm wide in var. anomalum), mostly glabrous on the upper surface, finely spreading-hirtellous to glabrous on the lower surface; inflorescence at first generally compact and with contiguous umbellets, but soon becoming looser, the rays elongating unequally, the longer ones mostly 2-10 cm long at maturity, the pedicels (1) 2-6 (10) mm long at maturity; involucel of a few long, slender bractlets; petals yellow; fruit oblong to broadly elliptic, 7-15 (20) mm long, narrowly to very broadly winged, glabrous to occasionally minutely puberlent or granular-scabrous, the oil-tubes solitary in the intervals, 2 on the commissure, 2n = 22.

Cronquist, A., A.H., Holmgren, J.L., and Holmgren, P.K. (1997) "Intermountain Flora" pg. 418, vol. 3 part A, The New York Botanical Garden New York.