Trifolium dubium Sibth.
suckling clover
Annual; stems sparsely to densely hairy, procumbent or ascending, not rooting at nodes. Lvs glabrous to moderately hairy on petioles and undersurface of leaflets; petioles 1-5-(20) mm long; leaflets obovate, usually emarginate, occasionally obtuse, rarely some leaflets shortly mucronate, cuneate at base, finely serrate, c. 3-12 mm long; lateral veins thin and straight to leaflet margin; petiolules distinctly unequal on most lvs; lateral petiolules < 1 mm long; terminal petiolule up to 2-(3) mm long; stipules ovate, acute. Infls axillary, racemose, cylindric to globose, pedunculate, much > lvs; fls 5-20-(25); pedicels 0-1 mm long; bracts subtending fls reduced to glandular hairs. Calyx ± glabrous, occasionally sparsely hairy, 5-veined, not inflated at fruiting; throat open, glabrous; calyx teeth unequal, < corolla, erect at fruiting; 3 lower teeth longer, lanceolate, ± = or somewhat > tube; 2 upper teeth triangular and < tube; sinuses obtuse. Corolla yellow, persistent, 2.5-4 mm long. Pod glabrous, straight, > calyx, 2-3 mm long, 1-seeded; seeds c. 1-1.5 mm diam.
N.; S.: common throughout; St.: disturbed lowland areas; K., Ch., C.
Europe to Caucasia 1869
Growing in a wide range of habitats, especially waste places, pasture, lawns, gardens, and cultivated land.
FL Oct-Jun.
Suckling clover is the most common of the 4 naturalised yellow-flowered clovers; it is distinguished from T. campestre, the only other sp. with unequal petiolules, by the fewer-flowered heads (Plate 13) and the less obviously sulcate corolla. In reduced plants the petiolules of most lvs may be ± equal so that confusion with T. micranthum may result, however, heads of T. micranthum have fewer than 7 fls and at least some lvs with unequal petiolules can usually be found on reduced plants of T. dubium. Suckling clover is a troublesome lawn weed and is often an impurity in crop seed. The sp. has been previously known in N.Z. as T. minus.
