Trifolium obtusiflorum is a species of clover known by the common name clammy clover. It is native to California in the Peninsular, Transverse, Sierra Nevada, and the California Coast Ranges and Cascade Range into southwestern Oregon. It grows in moist habitat such as marshes and streambanks, and disturbed areas. Trifolium obtusiflorum is an annual herb growing erect in form. It is hairy, glandular, and sticky in texture. The leaves are made up of sharply toothed, pointed oval leaflets up to 4 centimeters in length. The inflorescence is a head of flowers up to 3 centimeters wide with a base of toothed bracts. Each flower has a calyx of sepals with lobes narrowing into bristles. The flower corolla may be nearly 2 centimeters long and is pink and purple with a white tip.