It is a common plant in the granite foothills and mountains of the Sierra Nevada and southern Cascade Range, from Tulare County to Siskiyou County, from elevations of 800 to 3,500 metres (2,600 to 11,500 ft).

In Nevada, it is reported only from Washoe County in the northwestern part of the state.

[2][3][4][5][6] The red Sierra onion, Allium obtusum, grows from a bulb one or two centimeters wide and bears a scape which can range from 2 to 17 cm tall.

Unlike Allium campanulatum, A. obtusum has leaves that do not wither before the flowers bloom.

Atop the scape is an umbel of up to 60 flowers, each of which may be 4 to 12 millimeters wide.