Rose Clover

Annual, Herbs, Taproot present, Nodules present, Stems erect or ascending, Stems less than 1 m tall, Stems solid, Stems or young twigs sparsely to densely hairy, Leaves alternate, Leaves petiolate, Stipules conspicuous, Stipules green, triangulate to lanceolate or foliaceous, Stipules setiform, subulate or acicular, Stipules persistent, Stipules clasping stem at the base, Stipules adnate 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 hairy, Petals separate, Corolla papilionaceous, Petals clawed, Petals pinkish to rose, Petals red, 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, Seeds cordiform, mit-shaped, notched at one end, Seed surface smooth, Seeds olive, brown, or black.

Trifolium hirtum is a species of clover known by the common name rose clover. It is native to Europe, Western Asia, and North Africa. It is present elsewhere as an introduced species and it is cultivated as a cover crop and animal fodder. It was introduced to California from Turkey in the 1940s as a forage crop, and today it is a widespread roadside weed there.

It is a hairy annual herb growing erect in form. The leaves have oval leaflets up to 2.5 centimeters long and bristle-tipped stipules. The inflorescence is a head of flowers about 1.5 centimeters wide. Each flower has a calyx of sepals with long, needlelike lobes that may harden into bristles with age. The calyces are coated in long hairs. The flower has a pink corolla 1 or 1.5 centimeters long.