Epilobium brachycarpum, autumn willowherb

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Intermountain Flora
Taprooted annual, 2-10 (20) dm tall; herbage glabrous below, often glandular-puberulent above, the stems with an exfoliating outer layer; stems freely branched at least when well developed; leaves alternate almost throughout, short-petiolate or sessile, linear to narrowly elliptic or lanceolate the principal ones of the main stem 2-7 cm long and 2-8 mm wide, often folded along the midrib, entire or irregularly toothed, and with a firm, brownish apical gland, often soon deciduous, those on the lateral branches often smaller, the fascicles of reduced leaves commonly present in teh main axils; racemes terminating the numerous branches, lax, few-flowered, often giving the effect of a diffusely branched panicle; pedicels filiform, mostly 5-20 mm long, gthe subtending bract often adnate to the lower part of the pedicel; floral tube 1-8 mm long; sepals 1-3 mm long; petals pink or white, 2-6 mm long; pollen in monads; stigma with 4 very short, erect lobes; capsule 1.5-3 cm long, beaked, glabrous or more often slightly glandular-puberulent; seeds numerous, mostly 1.5-2.5 mm long, with a prominent constriction toward the micropylar end, faintly papillate, the coma deciduous; 2n = 24.

Cronquist, A., Holmgren, N.H., and Holmgren, P.K. (1997) "Intermountain Flora" pg. 240, vol. 3 part A, The New York Botanical Garden New York.