It is a subshrub native to the southwestern United States and northern Mexico, and can be found in arid grassland and desert sand dune habitats.

It can be toxic to livestock in large quantities, due to the presence of saponins and high concentrations of selenium.

[2] G. microcephala typically flowers July to October,[3] but this can vary depending on the amount of precipitation.

[1][6][7] It occurs in a variety of ecoregions, such as arid grasslands, chaparral, sand dunes, and oak or oak-pine woodlands.

[14] Toxicity symptoms include abortion and death;[11][15] as little as 9 kilograms (20 lb) of fresh G. microcephala consumed by cattle in seven days can cause abortions, and in cattle, sheep, and goats consuming ten to twenty percent of their body weight in two weeks can cause death.

[17] Fire kills or severely damages G. microcephala, allowing controlled burns to be used in the management of its populations.