Cheesebush, which bears the scientific name ambrosia salsola and is also commonly called winged ragweed, burrobush, white burrobrush, and desert pearl, is a foul-smelling, scraggly perennial shrub in the sunflower family which grows in the Mojave Desert and is also common in other deserts of the southwestern United States and northwestern Mexico.
Cheesebrush grows to typically two feet to three feet in height, although on occasion it will grow as high as 60 inches, or when sprawling, eight feet high. It is drought deciduous, which means it drops about half of its leaves and some of its twigs in hot, dry summer conditions.
It is common on sandy desert flats, desert dry washes, and is weedy in disturbed sites in creosote bush scrub, shadscale scrub, Joshua tree woodland, and Pinyon juniper woodland, ranging from Inyo County, California, to northwestern Mexico.
It grows in sandy and gravelly soil, and sometimes on lava formations at elevations of 650–6000 feet.
Cheesebush thrives in alkaline environments, and sites where other plants have died out.
The plant has thin stems and narrow, needlelike leaves. The linear leaves are thread-like (filiform), sometimes up to 2.6 inches long but a mere 0.06 inches across.
The foliage and stem tips have a foul, pungent, cheese-like scent when crushed, a trait which gives the plant the common name “cheesebush.”
Cheesebush flowers from March to June. Numerous small, cuplike male flowers grow in spike-like clusters above the female heads growing in the leaf axils. All pistilate (female) flower heads contain only one flower, while all staminate (male) heads may contain 5-15 flowers.
It is covered in plentiful white or yellow flowers and then pearly, winged fruits in white, yellow, or pink.
This species easily hybridizes with the white bur-sage (Ambrosia dumosa).
A powder made from the dry roots was used to treat wounds by Native Americans. The seeds can be toasted or eaten raw. The Seri Indians of Sonora, Mexico, use white burrobrush twigs and stems in several remedies. The twigs or leaves are mixed with all-thorn (Koeberlinia spinosa) twigs, boiled, and the tea taken to treat skin rashes. Seri also drank the tea to relieve pain in the lungs and trachea, and to reduce swelling. Additionally, they used white burrobrush as a remedy for rheumatism.