Erythronium grandiflorum (dogtooth violet)

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Intermountain Flora
Tall, usually erect perennial herbs 1-3 (3.5) dm tall with slender scapes arising from a long slender corm; leaves green, not mottled, narrowly to broadly oblong-elliptic, 1-2 dm long, 1-5 cm wide, narrowing gradually to a broad petiole or subsessile, the apex acuminate; flowers 2-4 (5) on nodding, naked peduncles, pale yellow to golden (ours) or white, the base lighter within and streaked with green without, the tepals (2) 2.5-3.5 (4) cm long, 4-7 mm wide, lanceolate, spreading and becoming reflexed from near the base with the basal appendages well developed, globular but not strongly inflated; stamens long exserted from the reflexed tepals but still shorter than the tepals, the filament erect, slender, not concealing the ovary nor surrounding the style, the anther white, yellow, red or somewhat purplish, (8) 10-12 mm long before dehiscence; ovary with elongated styles projecting the 3 spreading, 1-2 (4) mm long stigmatic lobes beyond the dehiscing anthers; capsules cylindric-clavate, 3-6 cm long, tan to dark brown; 2n = 24.

Cronquist, A., Holmgren, A.H., Holmgren, N.H., Reveal, J.L., and Holmgren, P.K. (1977) "Intermountain Flora" pg. 492, vol. 6, The New York Botanical Garden New York.