Duration: Annual Nativity: Native Lifeform: Forb/Herb General: Stems erect to prostrate annual, herbs or small shrubs 10-50 cm tall. Leaves: Trifoliate leaves, leaflets linear to linear-lanceolate, not more than 5 mm wide, to 4 cm long, bright green with reticulate veins, sparsely pilose to subglabrate above, paler to pubescent beneath. Flowers: In terminal or axillary racemes, simple or compound, corolla purplish 3-3.5 mm long. Fruits: Flat loments with 1-4 single seeded segments, segments less than 5 mm long, orbicular to elliptic, indehiscent, glabrous, margins flat, not contorted or nearly so. Ecology: Found on slopes, mesas, and grasslands, from 3,500-6,500 ft (1067-1981 m); flowering August-September. Notes: Look to the glabrous, orbicular to elliptic loments with flat margins to help identify this species. These plants can be vining, and the leaves can appear as three linear, palmate leaflets. Ethnobotany: There is no specific use recorded for this species, however the genus was used as an infusion to treat vomiting and colds and as a wash for sores. Etymology: Desmodium is from the Greek desmos for chain, which is a reference to the jointed seed pods, while rosei is named for Lewis Samuel Rose (1893-1973) an American botanical collector. Synonyms: None Editor: LCrumbacher, 2011