Trifolium tomentosum

Herbs annual, 10–20 cm, glabrous or sparsely hairy. Stems prostrate, ascending, or erect, branched. Leaves palmate; stipules ovate or triangular-lanceolate, 0.4–1.2 cm, margins entire, apex acute or acuminate; petiole 0.5–7 cm; petiolules to 1 mm; leaflets 3, blades obovate, obcordate, or elliptic, 0.4–1.5 × 0.3–1 cm, base cuneate, veins moderately prominent, margins denticulate, apex rounded or emarginate, surfaces sparsely hairy abaxially, glabrous adaxially. Peduncles 0.5–1.5 cm. Inflorescences axillary, 10–20-flowered, subglobose, soon becoming globose, flowers resupinate, calyces densely white-woolly, compacted, inflated, 0.5–1.5 × 0.5–1.5 cm; involucres a narrow rim, 0.2 mm. Pedicels slightly reflexed, to 0.5 mm; bracteoles cup-shaped, membranous, 0.2 mm. Flowers 3–7 mm; calyx tubular, inflated in fruit, markedly asymmetric-bilabiate, 2–6 mm, woolly adaxially, veins 5–10, connected by lateral veins, tube 1.5–2.5 mm, 4–5 mm in fruit, lobes unequal, subulate, shorter than tube, adaxial spreading or curved, orifice open, abruptly constricted in fruit; corolla pink, 3–6 mm, banner ovate, 3–6 × 3–6 mm, apex emarginate to crenulate. Legumes ovoid to globose, 2–3 mm. Seeds 1 or 2, yellow to brown, mottled, mitten-shaped, 0.9–1.1 mm, smooth, glossy. 2n = 16.

Phenology: Flowering Feb–Apr.
Habitat: Sandy lawns, fields, meadows, roadsides, clay soils among vernal pools.
Elevation: 0–400 m.

Introduced; Calif., Fla., Mass., N.C., S.C., s Europe (Mediterranean), sw Asia, n Africa, Atlantic Islands (Azores), introduced also in South America (Chile), s Africa, Pacific Islands (New Zealand), Australia.

Discussion

Trifolium tomentosum is occasionally cultivated as a forage crop (F. J. Hermann 1953) and is becoming weedy in the flora area and in Australia (R. P. Randall 2002).

Selected References

None.

Lower Taxa