Chrysothamnus nauseosus, also known as rubber rabbitbrush, gray rabbitbrush, or Chamisa, is a shrub of the genus Chrysothamnus that grows in the arid regions of western North America. The large number of identified subspecies (28 named), is the result of significant variation within the species.

It is a shrubby, 12- to 90-inch (30–230 cm) perennial, producing pungent-smelling, golden-yellow flowers in late summer and early fall. Flower heads are numerous and occur in umbrella-shaped terminal clusters. The shrub reproduces from seeds and root sprouts. Leaves, depending on the subspecies, are long and narrow to spatula-shaped. Both the flexible (rubbery) stems and the leaves are greenish-gray with a soft felt-like covering.

Along with associated species, like big sage and western wheat grass, rubber rabbitbrush is a significant source of food for browsing wildlife on winter ranges. Dense stands of this species often grow on poorly managed rangelands, in disturbed areas along roadways and on abandoned agricultural property.

Rabbitbrush has gained popularity as an ornamental xeriscaping shrub in areas where water conservation is important. It thrives in a wide range of coarse, alkaline soils that are common to desert environments. Pruning the shrub back to several inches in early spring, before new growth begins, may help improve the shrub's ornamental value.

Specimens growing in Bayo Canyon, near Los Alamos, New Mexico, exhibit a concentration of radioactive strontium-90 300,000 times higher than a normal plant. Their roots reach into a closed nuclear waste treatment area, mistaking strontium for calcium due to its similar chemical properties. The radioactive shrubs are "indistinguishable from other shrubs without a Geiger counter."

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