Allium falcifolium is a species of wil onion known by the common name scytheleaf onion. It is native to northern California and southern Oregon, where it grows in heavy, rocky soils, especially serpentine soils. The scytheleaf onion grows from a reddish-brown bulb one to two centimeters wide. The reddish or yellowish green stem is flattened such that it is thick in the center and thin along the edges. There are usually two leaves, which, as its common name suggests, are curved like the blade of a scythe. The stem is short and topped with an inflorescence of 10 to 30 flowers, each of which is one to one and a half centimeters wide. Each flower has six pinkish, red-purple, or white-streaked purple tepals.