Annuals, sometimes biennials; roots taproots, stout. Stems 0–10 mm. Leaves 20–80(–115) × 5–15 mm; blade lanceolate, margins usually 1- or 2-pinnatifid, veins conspicuous or not, surfaces villous, hairs septate, sometimes glabrate. Scapes decumbent, sometimes erect, 15–150(–210) mm, villous. Spikes decumbent, sometimes erect, greenish, purplish, or brownish, (15–)30–300 mm, densely flowered; bracts ovate to lanceolate, 1.5–2 mm, length 0.5–0.6 times sepals. Flowers: sepals 2–3 mm; corolla radially symmetric, tube hairy, lobes reflexed, 1 mm, base obtuse; stamens 4. Seeds (2–)4 (plus 1 smaller, distal one of different shape), 1–1.5 mm. 2n = 10, 20, 30 (all Eurasia).
Phenology: Flowering summer.
Habitat: Moist, gravelly or sandy soils.
Elevation: 0–200 m.
Introduced; Greenland, B.C., Man., Calif., Mass., N.J., N.Y., Oreg., Pa., Tex., Wash., Eurasia, Africa, introduced also in s South America.