Thimble Clover

Annual, Herbs, Taproot present, Nodules present, Stems erect or ascending, Stems or branches arching, spreading or decumbent, Stems prostrate, trailing, or mat forming, Stems less than 1 m tall, Stems solid, Stems or young twigs sparsely to densely hairy, Stem hairs hispid to villous, Leaves alternate, Leaves petiolate, Stipules conspicuous, Stipules green, triangulate to lanceolate or foliaceous, Stipules persistent, Stipules clasping stem at the base, Stipules adna te to petiole, Leaves compound, Leaves palmately 2-3 foliate, Leaflets dentate or denticulate, Leaflets 3, Leaves glabrous or nearly so, Inflorescences racemes, Inflorescences globose heads, capitate or subcapitate, Inflorescence axillary, Bracteoles present, Flowers zygomorphic, Calyx 5-lobed, Calyx glabrous, Petals separate, Corolla papilionaceous, Petals clawed, Petals white, Petals pinkish to rose, Petals bicolored or with red, purple or yellow streaks or spots, Banner petal narrow or oblanceolate, Wing petals narrow, oblanceolate to oblong, Wing petals auriculate, Wing tips obtuse or rounded, Keel tips obtuse or rounded, not beaked, Stamens 9-10, Stamens diadelphous, 9 united, 1 free, Filaments glabrous, Style terete, Fruit a legume, Fruit unilocular, Fruit indehiscent, Fruit oblong or ellipsoidal, Fruit orbicular to subglobose, Fruit or valves persistent on stem, Fruit enclosed in calyx, Fruit glabrous or glabrate, Fruit 1-seeded, Fruit 2-seeded, Seeds cordiform, mit- shaped, notched at one end, Seed surface smooth, Seeds olive, brown, or black, Seed surface mottled or patchy.

Trifolium microdon is a species of clover known by the common name thimble clover. It is native to western North America from British Columbia to southern California, where it grows in many types of habitat, including disturbed areas. It is an annual herb taking a decumbent or erect form. It is coated in hairs. The leaves are made up of oval leaflets with notched or flat tips, each measuring up to 1.5 centimeters long. The inflorescence is a head of flowers borne in a deep bowl-like involucre of bracts that can nearly envelop the whole head. The flower corollas are white to pink and about half a centimeter long.