2. Ericameria arborescens (A. Gray) Greene, Man. Bot. San Francisco. 175. 1894.
Linosyris arborescens A. Gray in W. H. Emory, Rep. U.S. Mex. Bound. 2(1): 79. 1859; Haplopappus arborescens (A. Gray) H. M. Hall
Plants 10–500 cm. Stems erect to spreading, green when young, fastigiately branched, glabrous or sparsely hairy, gland-dotted, resinous. Leaves mostly ascending to spreading, older deflexed; blades filiform (sulcate to concave), 25–90 × 0.5–3 mm, midnerves obscure to evident, apices acuminate to attenuate, often mucronate, faces glabrous or sparsely hairy, gland-dotted (in deep, circular pits), resinous; axillary leaf fascicles sometimes present. Heads in rounded, cymiform arrays (to 10 cm wide). Peduncles 1–15 mm (bracts 0–7, scalelike, resembling phyllaries). Involucres turbinate to subcampanulate, 4–6 × 3.5–4.5 mm. Phyllaries 20–25 in 3–4 series, tan, narrowly triangular to lanceolate, 1.5–5 × 0.5–1 mm, unequal, mostly chartaceous, midnerves evident, raised, mostly uniform in width to slightly dilated apically, (margins membranous, fimbriate) apices erect, acute, abaxial faces resinous. Ray florets 0. Disc florets 10–25; corollas 4–5 mm. Cypselae tan to brown, narrowly turbinate, 2–3 mm (5-ribbed), hairy; pappi tan, 3.5–4.5 mm. 2n = 18.
Flowering late summer–fall. Dry foothill slopes, in chaparral; 90–2000 m; Calif., Oreg.