Stout, 3-10 dm, almost always unbranched; herbage glabrous; lvs yellow-green, spreading, lanceolate or lance-ovate, 5-15 נ1.5-5 cm, long-acuminate, widest near the broadly rounded or subcordate sessile base, often 3-nerved; infl usually compact and many-fld; cal-lobes lance-ovate to deltoid-ovate, 4-15 mm, often spreading, with a prominent keel decurrent onto the tube; cor yellowish-white or greenish-white, 3.5-5 cm, narrowly open, its broadly ovate lobes commonly 4-6 mm longer than the oblique, ±erose plaits; anthers connate. Moist prairies and open woods; irregularly from s. Ont. to Pa. and N.C., w. to Minn., e. Neb., e. Kans., and n. Ark., more abundant westward. Sept., Oct. (G. alba Muhl., nomen subnudum)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.