Phacelia heterophylla, varileaf scorpionweed

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Intermountain Flora
Biennial or short-lived perennial from a taproot, with a single erect, often stout stem mostly 2-12 dm tall, or this often surrounded at the base by several ascending, lesser stems; herbage green or grayish with pubescence, but scarcely silvery, often evidently spreading-bristly, the stem generally covered with fine, short, loose, or spreading, often glandular hairs in addition to the longer bristles; leaves prominently veined, the lower petiolate, the upper progressively less so; basal leaves larger or smaller than the well developed cauline ones; some of the better-developed leaves ordinarily with 1 or 2 (4) pairs of lobes or leaflets at the base of the blade, these sometimes fairly large, but still much smaller than the terminal segment, rarely all the leaves entire; inflorescences densely bristly and short-hairy, characteristically elongate and narrow, somewhat virgate, but sometimes more openly branched, or shorter and more compact; corolla dull whitish or ochroleucous to occasionally purplish, 3-6 mm long and broad; filaments conspicuously exserted, hairy near the middle; ovules 4, often only 1 or 2 maturing; seeds 2-2.5 mm long. Diploids and tetraploids based on x = 11.

Cronquist, A., Holmgren, A.H., Holmgren, N.H., Reveal, J.L., and Holmgren, P.K. (1984) "Intermountain Flora" pg.181-182, vol. 4, The New York Botanical Garden New York.