Annual; stems 1-3 dm, glandular-pubescent; lvs lanceolate to oblanceolate, 2-5(-6) cm, narrowed from near or above the middle to the base; pedicels very slender, widely divergent, 1-2 ( + ) cm; bractlets equaling or surpassing the cal; sep lanceolate, 4-6 mm; cor 8-10 mm, the lobes white, the tube yellowish; fr 3-5 mm; 2n=16. Wet soil; Que. to B.C., s. to Ga. and Ariz.; our most abundant sp. May-July, also again in autumn, and often then with cleistogamous fls. (G. virginica, misapplied)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.
©The New York Botanical Garden. All rights reserved. Used by permission.
General: Annual, 5-20 cm tall; stems ascending to decumbent, simple to branched; herbage glandular-puberulent to sometimes nearly glabrous; roots fibrous. Leaves: Cauline, opposite, oblanceolate to obovate, 1-5 cm long, mostly 3-10 mm wide, glandular-puberulent to nearly glabrous, margins minutely dentate in the upper half or sometimes entire throughout, apex acute, base slightly clasping; blades sessile. Flowers: Inflorescence a head-like spike, these 2-10 flowered, terminating the branches; outer bracts of 1 or more subtending each spike, these leaf-like, 1-2.5 cm long, similarly divided as the leaves, often more so, the divisions filiform; inner bract subtending each flower narrowly lanceolate, 1.5-2.5 cm long, margins entire or sometimes pinnately divided into 3-5 apical lobes; calyx narrowly lanceolate to linear, 1.5-2 cm long, the apex cleft; corolla tubular, bilabiate, 1.6-2.4 cm long, yellow to purplish or marked with purple, the lips nearly equal; stamens 4; flowers July-October. Fruits: Capsule, mostly septicidal, globose-ovoid, 3.5-5.5 mm long; seeds numerous, minute, light brown. Ecology: Moist habitats, pond and lake margins, often in mud; 2000-2400 m (6500-8000 ft); Apache, Coconino, and Navajo counties; widely distributed throughout North America. Notes: na Editor: Springer et al. 2008