Erigeron glabellus, smooth fleabane

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Intermountain Flora
Fibrous-rooted biennial or often short-lived perennial herb from a crown or a simple or slightly branched caudex; stems 1-6 dm tall, usually erect from the base; herbage and involucre thinly to copiously strigose with appressed or closely ascending hairs, not glandular; leaves basally disposed, the lowest ones oblanceolate, tapering to a petiolar or narrow but sessile base, 4-15 cm long overall, 3-20 mm wide, persistent, often forming a basal tuft; cauline leaves mostly sessile, progressively reduced upwards, though often fairly ample; heads 1-15, subnaked-pedunculate; involucre 5-9 mm high, hairy but not glandular, its bracts commonly with a tan to red-brown midvein or midstrip, subequal or the outer often a little shorter than the inner; rays numerous, ca 125-175, blue to pink or white, 8-15 mm long, ca 1 mm wide; disk-corollas 4-5.5 mm long; achenes 2-nerved; outer pappus setulose and sometimes obscure; 2n = 18, 27, 36.

Cronquist, A., Holmgren, A.H., Holmgren, N.H., Reveal, J.L., and Holmgren, P.K. (1994) "Intermountain Flora" pg. 314, vol. 5, The New York Botanical Garden New York.