Sand esparcet

Onobrychis arenaria, the sand esparcet or sand sainfoin, is a perennial herb in the legume family (Fabaceae), native to the dry steppes and sandy grasslands of central and eastern Europe extending across the Pontic-Caspian region into southern Siberia, the Caucasus, and Central Asia. Plants develop a deep woody taproot and erect to ascending stems 30-80 cm tall that are slightly hairy and somewhat branched above. The leaves are alternate and imparipinnate, 5-15 cm long, bearing 6-12 pairs of opposite, narrow oblong-elliptic to linear leaflets 1-3 cm long, sparsely silky-hairy beneath; stipules are scarious and brownish. Inflorescences are dense terminal spike-like racemes 5-15 cm long on long peduncles, bearing many pea-flowers; each flower is 8-12 mm long with a bright pink to rose-purple standard veined with darker lines, slightly shorter wings, and a deeper-coloured keel. The fruit is a small indehiscent single-seeded pod 4-6 mm in diameter, the surface reticulately ridged and armed with short conical teeth or spines along the lower margin. The species is valued as drought-tolerant pasture and hay legume on light, calcareous soils.