Smithsonian Contr. Knowl. 3(5): 87. 1852.
Shrubs, 60–120 cm. Stems much branched, pubescent, gland-dotted. Leaves alternate; petioles 2–5 mm; blades 3-nerved from bases, oblong to broadly ovate, 6–15 × 5–9 mm, bases narrowly cuneate, margins irregularly dentate, apices acute to obtuse, faces sparsely pubescent, gland-dotted. Heads in (leafy) paniculiform or racemiform arrays. Peduncles 0.5–2.5 mm, glandular-viscid. Involucres cylindric, 6–8 mm. Phyllaries 15–25 in 4–6 series, stramineous, 3–5-striate, unequal, (gland-dotted) margins scarious (apices obtuse to acute); outer ovate, inner lanceolate. Florets 8–14; corollas pale yellow-green, often purple-tinged, 4.8–5.7 mm. Cypselae 2.5–3 mm, sparsely pubescent or strigose; pappi of 24–28 tawny, barbellate bristles. 2n = 18.
Phenology: Flowering Aug–Nov.
Habitat: Dry slopes, streambeds (arroyos)
Elevation: 1300–1900 m
N.Mex., Tex., Mexico.