Flora of the Hawaiian Islands
Dicotyledon Literature for Medicago polymorpha
Wagner et al., 1990, 1999.
   Fabaceae -- The Pea Family Bibliography
      Medicago polymorpha

Common name(s): bur clover
General Information
DistributionNative to Europe and temperate Asia to China and Japan, also in northern India, widely cultivated as a fodder plant.In the Hawaiian Islands, naturalized on Midway, Kaua`i, O`ahu, Moloka`i, Lana`i, Maui, Hawai`i.

Annual herbs; stems prostrate, up to 4 dm long, branched, subglabrous, with a few long hairs on petiolules, lower surface of leaflets, and calyx.
Leaflets obovate-cuneate, 7-25 mm long, 5-23 mm wide, glabrate, margins dentate in upper 1/2, apex rounded to truncate or emarginate, stipules narrowly elliptic to narrowly ovate, laciniate.
Flowers (1-)3-5(-8) in racemes; corolla yellow, 3-4.5 mm long.
Pods 4-8(-10) mm in diameter, spirally twisted in (1.5-)3-4(-6) turns, glabrous or subglabrous, transverse veins prominent, anastomosing, groove between submarginal and marginal vein wide, with nearly straight prickles 2-3 mm long, arising from the submarginal and marginal veins.
Seeds several.
2n = 14, 16