It is native to the southwestern United States and northwestern Mexico, where it grows in many types of desert habitat.

It is an annual herb producing a slender, rough-haired stem, generally upright to erect in form to a maximum height of about 21 centimeters.

The small, pointed linear leaves alternately arranged along the stem.

The flower has small green sepals and a rounded white corolla.

The fruits, borne in groups of four, are curved nutlets fringed with flat teeth, each measuring 2.5 to 4 millimeters long.