Trifolium macrocephalum is a species of clover known by the common name largehead clover. It is native to the northwestern United States from Washington to northern California to Idaho, where it occurs in several types of habitat, including sagebrush and mountain woodlands. It is a rhizomatous perennial herb taking an upright form. The herbage is hairy. The leaves are made up of 5 to 9 thick oval leaflets each measuring up to 2.5 centimeters in length. The inflorescence is crowded, egg-shaped and up to 5 or 6 centimeters long. Each flower has a calyx of sepals with lobes narrowing into bristles which are coated in long woolly hairs. The flower corolla may be nearly 3 centimeters in length and is pink in color, or sometimes bicolored.