File:Trifolium dubium flower NC7.jpg

English: Introduced, cool-season, annual, low-growing, hairless legume, with prostrate to ascending stems. Leaves have 3 leaflets, each oblong to round and 4-13 mm long. The central leaflet has a distinctly longer stalk than the lateral ones. Flowerheads are loose to somewhat dense hemispherical clusters (6-7 mm long) of 3-20 yellow pea-like flowers. Flowering is in spring. A native of Europe, it is found in pastures, woodlands, lawns and roadsides. Although it often occurs at reasonably high density in short pastures, productivity is low and it has a high proportion of stem to leaf. It is palatable and grows from autumn to early summer (very dependent on rainfall), but only produces useful amounts of feed in spring. Requires moist soil for growth, so tends to burn-off rapidly in late spring as temperatures rise and soil moisture often remains low. Growth increases with applied phosphorus as long as pastures are kept short in late winter and early spring, but the response is likely to be too small to be economic.