It is endemic to Tuolumne County, California, where it is known only from a small section of the Sierra Nevada foothills at Rawhide Hill and the Red Hills. It is a plant of serpentine soils.Allium tuolumnense is a rare species of wild onion, known by the common name Rawhide Hill onion.
This onion, Allium tuolumnense, grows from a reddish-brown bulb one to two centimeters long, producing a slender erect stem up to 50 centimetres (20 in) tall and usually a single leaf approximately the same length.
The stem is topped with a hemispheric inflorescence holding 20 to 60 flowers, each on a pedicel one or two centimeters long. Each flower is just under a centimeter wide when fully open, with six white or pink oval-shaped tepals. There are six stamens and the ovary has six pointed crests.