Trifolium campestre is an annual herb 10-40 cm tall, often spreading, freely branched, stems hairy, slender, becoming dark, leafless with age (away from growing tips), stipules irregularly ovate, rounded at base, half as long as leaf stalk.
Leaves alternate, 3-parted, terminal leaflet stalk 0.1-0.3 cm long, leaflets oblong to wider above middle, (obovate), to 1.5 cm long.
Flowers yellow, bilaterally symmetrical, pea-flower-shaped, rather papery, 0.4-0.5 cm long, the largest petal (standard) much larger than others, widest above middle, with fan-shaped vein pattern (use hand lens); flower heads round to short-cylindrical, to 1.5 cm long of 20-30 flowers, compact.
Fruit dry, pods straight, short.
Wetland status: NL.
Frequency in NYC: Infrequent, but widely distributed.
Habitat: Open, disturbed areas, roadsides, fill sites.
Notes: Foliage eaten by rabbits and woodchucks, seeds eaten by numerous birds and small mammals (Martin et al. 1951).