Trifolium striatum

Herbs usually annual, rarely biennial, 10–50 cm, villous. Stems erect, ascending, or decumbent, branched from base. Leaves palmate; stipules lanceolate-ovate, 0.9–1.1 cm, margins entire, apex acute-acuminate, setaceous, ciliate; petiole 0.5–5 cm; petiolules 0.5 mm; leaflets 3, blades obovate to oblong, 0.9–1.6 × 0.4–1 cm, base cuneate, veins fine, margins denticulate, apex obtuse, obcordate, or emarginate, surfaces hairy. Peduncles 0–1 cm. Inflorescences axillary or terminal, solitary or paired, 20–60-flowered, ovoid or oblong, 0.8–1.6 × 0.6–1 cm; involucres absent. Pedicels absent; bracteoles absent. Flowers 5–7 mm; calyx ellipsoid to urceolate, 3–4 mm, hairy, veins 10, tube 2–3 mm, lobes erect or spreading, unequal, abaxial longest and equal to tube, subulate, orifice open; corolla pink, 25–35 mm, banner oblong, 2.5–3.5 × 1.5–2 mm, apex retuse. Legumes ovoid, leathery distally, transversely dehiscent, 2–2.5 mm. Seeds 1, tan or reddish brown, globose to ovoid, 1–1.5 mm, smooth, glossy. 2n = 14.

Phenology: Flowering May–Aug.
Habitat: Waste places
Elevation: 0–500 m.

B.C., Ala., Ark., Calif., Ga., Mass., Mo., N.J., N.Y., N.C., Okla., Oreg., Pa., S.C., Vt., Va., Wash., Europe, w Asia, nw Africa, introduced also in s South America (Chile), Pacific Islands (New Zealand), Australia.

Discussion

Trifolium striatum has been recorded as an occasional weed in the flora area, having been first collected on ballast in New Jersey in 1880. It is found sporadically as a weed of disturbed habitats and appears to be spreading rapidly. It has been called Pitts’s clover in the southern United States because it was discovered by J. D. Pitts in a field of crimson clover as a weed and he experimented with it as a forage plant (G. L. Fuller and B. H. Hendrickson 1928).

Selected References

None.

Lower Taxa