Annual herb 10 - 40 cm long Stem: angled, forking, slightly hairy. Leaves: opposite, minutely hairy along margin and sometimes short-haired, with the lower leaves more or less stalked and broadly inverted lance-shaped. The other leaves are stalkless, 1 - 7 cm long, 3 - 18 mm wide, oblong, and toothless or with a few teeth near the base. Flowers: borne terminally in a small compact cluster (glomerule), subtended by spoon-shaped bracts that are hairy along the margins, 1.5 - 2 mm across, with minute or absent sepals, white to pale bluish petals fused into a five-lobed funnel shape, and three stamens. Fruit: dry, yellowish, 2 - 4 mm long, three-chambered with one chamber fertile and one-seeded and the other chambers empty. The fertile chamber has a thick corky mass on its back.
Similar species: Valerianella species have non- or few-toothed stem leaves and tiny or absent calyx lobes. Neither Valerianella chenopodifolia nor Valerianella umbilicata have fruit with a corky mass on the fertile chamber.
Flowering: mid May to early June
Habitat and ecology: Introduced from Europe, this species is rare in disturbed areas.
Occurence in the Chicago region: non-native
Etymology: Valerianella is a diminutive of Valeriana, referring to the similarity between the two genera. Locusta means "growing in an enclosed area."
Annual 1-4 dm; lvs ciliolate and sometimes short-hairy, the lower broadly oblanceolate or broader, and ±petiolate, the others sessile and more oblong, entire or the upper with a few teeth near the base, 1-7 cm נ3-18 mm; cor white or pale bluish, 1.5-2 mm; fr 2(-4) mm, the fertile locule bearing a thick corky mass on the back; groove between the sterile locules narrow, shallow, and inconspicuous; 2n=14(-18). Moist, open places, often in disturbed soil; native of Europe, now widely established in the U.S. Apr.-June. (V. olitoria)
Gleason, Henry A. & Cronquist, Arthur J. 1991. Manual of vascular plants of northeastern United States and adjacent Canada. lxxv + 910 pp.