Herbs perennial, 10–40 cm, glabrous or glabrescent. Stems creeping, branched, rooting at nodes. Leaves palmate; stipules lanceolate, 0.9–1.3 cm, margins entire, apex short-subulate; petiole 5–20 cm; petiolules to 1 mm; leaflets 3, blades obovate, obcordate, or orbiculate, 0.6–4 × 0.4–2.5 cm, base cuneate, veins moderately prominent, margins serrulate distally, apex rounded, emarginate, or retuse, surfaces glabrous. Peduncles erect, from prostrate stems, 1.5–30 cm. Inflorescences axillary, 20–40+-flowered, globose, 1.5–3.5 × 1.5–3.5 cm; involucres absent. Pedicels strongly reflexed in fruit, elongate, 3–5 mm; bracteoles white, lanceolate, 1–2 mm. Flowers 8–13 mm; calyx campanulate, 3–5 mm, glabrous, veins 6–10, tube 1.5–2.5 mm, lobes unequal to subequal, adaxial shorter than tube, triangular-lanceolate, orifice open; corolla white, often pinkish in age, 4–12 mm, banner ovate-lanceolate or oblong, 4–12 × 1–4 mm, apex rounded. Legumes linear-oblong, 4–5 mm. Seeds 3 or 4, yellow, reddish brown, or light brown, ovoid-reniform, 1 mm, smooth, glossy. 2n = 16, 28, 32, 48, 64.

Phenology: Flowering Feb–Oct.
Habitat: Fields, lawns, roadsides, forest edges, waste places.
Elevation: 0–4000 m.

Distribution

• Generated Map
• Legacy Map

Introduced; Greenland, St. Pierre and Miquelon, Alta., B.C., Man., N.B., Nfld. and Labr., N.W.T., N.S., Ont., P.E.I., Que., Sask., Yukon, Ala., Alaska, Ariz., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Wyo., Eurasia, introduced also in South America, Africa, Pacific Islands.

Discussion

Trifolium repens may very well be the most important temperate pasture plant (M. J. Baker and W. M. Williams 1987) and has been considered the most important peren­nial pasture plant in North America (C. V. Piper 1924). It was introduced at least as early as the mid 1800s (R. N. Mack 2003) and spread so rapidly that it became known to Native Americans as White Man’s Foot Grass (W. Strickland 1801). It is morphologically diverse; most material from the flora area represents var. repens, but some specimens fit within the circumscriptions given by M. Zohary and D. Heller (1984) of var. giganteum Lagrèze-Fossat, with inflorescences to 3.5 cm diameter and leaflets nearly 4 cm; others have smaller, pale-pink petals with hairy petioles and pedicels, and approach var. biasolettii (Steudel & Hochstetter) Ascherson & Graebner (T. occidentale Coombe).

Selected References

None.

Lower Taxa

None.