Plants annual or biennial. Stems erect to prostrate, 2-25 cm. Leaf blades 3-24 mm. Flowers usually equaling or exceeded by bracts; hypanthium becoming strongly 10-ribbed in fruit, 1.2-2 mm; sepals not overlapping, spreading to erect in fruit, 1.5-4 mm, margins 0.1 mm or less wide, apex acute; stamens ca. 2 length of sepals. “Fruits” 3.2-5 mm including sepals. 2n = 44 (Europe).

Flowering winter-fall. Sandy fields, roadsides, weedy areas, lawns; 0-1500 m; introduced; Alta., B.C., N.B., Nfld. and Labr. (Nfld.), N.S., Ont., P.E.I., Que., Sask.; Ala., Ark., Calif., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., N.H., N.J., N.Y., N.C., Ohio, Okla., Oreg., Pa., R.I., S.C., Tenn., Vt., Va., Wash., W.Va., Wis.; Europe; w Asia; n Africa; widely naturalized elsewhere, including Mexico, Central America (Costa Rica), South America (Ecuador), e Asia (South Korea), Africa (Kenya, Republic of South Africa), Pacific Islands (New Zealand).