Herbs usually annual, rarely biennial, 20–60 cm, short-villous. Stems erect, unbranched or sparsely branched. Leaves palmate; stipules ovate, 1–2 cm, margins wavy or toothed, apex blunt or ± tapering distally; peti­ole 1–8 cm; petiolules 1 mm; leaflets 3, blades broadly ovate, 1–3 × 1–1.5 cm, base cuneate, veins fine, margins den­ticulate, apex emarginate or retuse, surfaces with spread­ing, pustulate-based hairs. Peduncles 2–10 cm. Inflo­rescences terminal, 25–100-flowered, oblong, 2–7 × 1–2.5 cm; involucres absent. Pedicels straight, 0.5 mm; bracteoles absent. Flowers 10–15 mm; calyx tubular-campanulate, 10 mm, villous, veins 10, tube 3–4 mm, lobes equal, longer than tube, spreading in fruit, orifice narrowly opening; corolla usually scarlet to red, rarely pink or white, 11–17 mm, banner oblong-elliptic, much longer than wing and keel petals, 10–16 × 2 mm, apex acute. Legumes ovoid, leathery distally, transversely dehiscent, 2.5–3 mm. Seeds 1, reddish, ellipsoid, 2–2.5 mm, smooth, glossy. 2n = 14.

Phenology: Flowering May–Aug.
Habitat: Meadows, roadsides, espe­cially in sandy soils.
Elevation: 0–1000 m.

Distribution

• Generated Map
• Legacy Map

Introduced; B.C., Ala., Ark., Calif., Conn., Del., D.C., Fla., Ga., Idaho, Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Vt., Va., Wash., W.Va., Wis., Europe, introduced also in s South America (Chile), e Asia (e China), s Africa, Pacific Islands (Hawaii, New Zealand), Australia.

Discussion

Trifolium incarnatum was introduced to the United States in 1818 as a forage crop and green manure crop; it is used commonly as a winter grazing crop and in roadside grass plantings as a nitrogen source, especially in the southeastern states (W. E. Knight 1985). Reports of T. incarnatum in Manitoba, Ontario, and Montana appear to have been based on cultivated specimens.

Selected References

None.

Lower Taxa

None.