Medicago sativa

5. M. sativa L., View in CoL Sp. Pl. 778 (1753).

More or less pubescent perennial up to 80 cm. Leaflets obovate to almost linear, longcuneate, dentate at apex; stipules lanceolate to linear-subulate, entire or dentate at base. Racemes 5- to 40-flowered. Pedicels short, stout, erect in fruit. Corolla (5—)6—11 mm. Legume nearly straight, falcate or in a spiral of 1-3 turns with a hole through the centre, glabrous, pubescent or glandular, not spiny; transverse veins anastomosing and forming a transversely or radially elongated network. Throughout most o f Europe, except the north and some islands; often naturalized. All except Az Fa Is Sb. Introduced in Fe.

Very variable, particularly in S. and S.E. Europe, where a number of distinct species have been recognized. In view of the overall variation and the known frequency of hybridization between M. sativa and M. falcata , two of the most distinct taxa, it seems best to treat them all as subspecies. Hybrids between subspecies with bluish and yellow corollas often have green or almost black corollas. The best-known of these is subsp. falcata x subsp. sativa (M. x varia Martyn ). What appear to be hybrids between subsp. glomerata and subspp. (a)-(c) have been called M. polychroa Grossh.

1 Corolla blue to purple 2 Corolla 7-11 mm (a) Subsp. sativa 2 Corolla 5—6(—7) mm 3 Legume falcate (b) Subsp. ambigua 3 Legume in a spiral of 2-3 turns (c) Subsp. caerulea 1 Corolla yellow 4 Legume nearly straight or falcate (d) Subsp. falcata 4 Legume in a spiral of l|- 3 turns (e) Subsp. glomerata

(a) Subsp. sativa; Corolla 7-11 mm, blue to violet; legume 4-6 mm in diameter, in a spiral of 1 |-3 | turns. 2n = 32. Cultivated as forage and naturalized throughout the range of the species. Origin uncertain.