Medicago sativa L.
lucerne
Erect or ascending, perennial herb; stems sparsely to moderately hairy in upper part, ± glabrous below. Lvs sparsely to densely hairy on petiole and undersurface of leaflets, ± glabrous above; petioles c. 4-20-(35) mm long; leaflets narrowly elliptic to obovate, usually obtuse, sometimes acute or emarginate, mucronate, obtuse to cuneate at base, irregularly serrate near apex, uniform in colour, c. 6-25-(35) mm long; terminal petiolule 2-6 mm long; lateral petiolules up to 1 mm long; stipules ovate to lanceolate, acuminate, entire or irregularly serrate. Infl. with 10-numerous fls; peduncles moderately hairy, > petioles; pedicel <, ± =, or > calyx tube. Calyx ± glabrous or hairy; calyx teeth triangular, acuminate, <, ± =, or > tube. Corolla usually purple or bluish, rarely pale blue or almost white, 7-12 mm long. Pod moderately hairy or ± glabrous, coiled in 11/2-3 turns with a hole through the centre, reticulately veined but otherwise smooth, 4-6 mm diam., 10-20-seeded; seeds yellow to brown, c. 3 mm long.
N.: locally established throughout but not collected from Taranaki; S.: Nelson City, Marlborough, Canterbury, Otago; K., Ch.
Mediterranean, W. Asia 1875
Waste places, cultivated land.
FL Nov-May.
Possibly poisonous (Connor 1977).
Lucerne has been cultivated for fodder since prehistoric times and is now grown widely in all temperate areas including N.Z. Many cultivated strains are derived to some extent from hybridisation with the hardier M. falcata L. and this may be reflected in some variation in fl. colour and pod shape. Pods are usually coiled in 11/2-3 turns (Fig. 65). Some naturalised plants are referable to M. × varia Martyn (M. falcata × M. sativa), a fertile hybrid which segregates and back-crosses with both parents. These plants have a yellow to purple, or yellow changing to purple corolla 7-12 mm long, with pods varying from ± straight to coiled in 2-3 turns. Small, E., Canad. J. Bot. 63: 1747-1752 (1985), discussed diploid and tetraploid forms of the various subspp. and hybrids of the M. sativa complex.