Description from
Flora of China
Trifolium [unranked] Melilotus Linnaeus, Sp. Pl. 2: 764. 1753 ["Meliloti"]; Brachylobus Dulac.
Annual or biennial herbs, taprooted, upright. Leaves pinnately 3-foliolate; stipules entire or nearly so, basally adnate to petiole; leaflets serrulate, lateral veins ending in teeth; stipels absent. Racemes axillary, slender, elongate; flowers numerous; bracts minute; bracteoles absent. Calyx teeth subequal. Corolla yellow or white, petals free from staminal tube, deciduous; standard ovate-oblong; wings narrowly oblong; keel broadly falcate. Stamens diadelphous; filaments capillary. Ovary sessile or shortly stipitate; ovules 2-8; style filiform, curved upward, often persistent. Legume obovoid or globose, slightly exserted from calyx, surface reticulate veined or wrinkled. Seeds 1 or 2, broadly ovoid, smooth or papillate.
These are fragrant herbs grown as green manure, forage crops, or bee plants.
About 20 species: temperate and subtropical N Africa, Asia, and Europe; four species in China.