Santa Fe Botanical Garden

Common name: rubber rabbitbrush, chamisa

Family: Asteraceae (Aster)

Synonym: Chrysothamnus nauseosus

Distribution: Central and Western North America, Northern Mexico

Habitat: Desert scrub, grasslands, pinyon-juniper and oak forests

Hardiness: USDA Zone 3 (-40 to -30 °F)

Life form: Deciduous shrub/sub-shrub

Occurrence in New Mexico: New Mexico native plant

Growing Conditions: The native distribution of rubber rabbitbrush ranges from Saskatchewan to southern British Columbia, south through the Great Plains to the uplands of west Texas and Baja California. It grows in dry grasslands, badlands, salt flats, open woodlands, foothills and mountains. It is often a dominant plant in sagebrush, pinyon-juniper and ponderosa pine communities. It grows from the lower-elevation Sonoran to subalpine zones. Rubber rabbitbrush favors sunny, open sites and is particularly common on disturbed sites. It is cold hardy to at least -40 degrees F, and is very tolerant of drought. It grows on a wide range of soils, including dry, sandy, gravelly or heavy clay soils with low fertility, but it will also grow in average garden soil. It is somewhat salt tolerant. It usually grows on moderately alkaline soils, but tolerates moderately acidic to strongly alkaline soils. Plants establish from seed, by sprouting from epicormic buds located on the stem and root crown, and can be propagated by stem cuttings. Rubber rabbitbrush usually produces an abundance of seed, but seed crops vary from year to year. Seeds are often dispersed by wind. They do not persist in soil in a seedbank. Seeds germinate in winter or spring after snowmelt; germination occurs over a broad range of temperatures but only with adequate moisture. Stratification is not necessary. Germination rates vary dramatically by seed source. Seeds from southern or warm desert populations germinate more rapidly, even at near-freezing temperatures, compared to those from northern or montane populations. Seeds retain good viability for up to 3 years, which declines rapidly thereafter. Established seedlings survive only if late spring rains replenish soil moisture and roots elongate before surface moisture is depleted. Rubber rabbitbrush is a fire-adapted species, and communities may be enhanced by fire. Although tops are burned, new growth sprouts from adventitious buds on the stem and root crown. Seeds dispersed by wind from other sites also shorten recovery time. Rubber rabbitbrush can form dense stands when planted along roadsides and other disturbed areas. It can be successfully seeded directly onto degraded lands resulting from surface mining. It is excellent for soil stabilization and erosion control and good for use on degraded winter ranges. Rubber rabbitbrush has a deep root system and plants produce large quantities of leaf litter, which produces soil mulch. Although rubber rabbitbrush may dominate a site, it generally is less competitive to understory plants than other shrubs such as sagebrush. Roots extend deeper in the soil than do those of perennial grasses and forbs. All varieties are considered to be slightly toxic to livestock. In general, wildlife and livestock forage only lightly on this plant during the summer, but it is important winter forage, particularly in depleted rangelands. Rubber rabbitbrush provides good cover for several species of nesting birds.

Description: Chamisa (also known as rubber rabbitbrush) is an erect round or pyramidal native shrub that typically reaches 1-8 feet in height and ¼-3 feet in diameter. Several branching, upright stems arise from the base. Leaves and stems may be covered with a felt-like layer of trichomes (hairs) giving them a grey-green color. Leaves are linear and narrow, arranged alternately along the stem. The plant produces pungent-smelling flat-topped or rounded clusters of small yellow flowers at the ends of the branches from August to October.