Shrubs or subshrubs, 20-100 cm (finely and densely branched from bases). Stems erect, green, slender and wandlike, striate-angled, glabrate proximally, hispidulous distally (near heads). Leaves present at flowering (reduced , sparse); sessile; blades (1-nerved) linear to linear-lanceolate, 5-17 × 1-2 mm (reduced distally to subulate bracts), margins entire, apices acute, faces glabrous (sometimes minutely papillose). Heads (on racemiform lateral branches) in paniculiform arrays. Involucres funnelform or campanulate; staminate 3-5.2 mm, pistillate 4-6 mm. Phyllaries lanceolate, 1-4 mm, margins scarious, medians green (hispid), apices acute to acuminate. Staminate florets (8-)12-18(-29); corollas 3.3-4.2 mm. Pistillate florets 8-18; corollas 2-2.8 mm. Cypselae 1.5-2.5 mm, 5-nerved, hispid; pappi 4.5-7 mm. 2n = 18. Flowering Jul-Aug. Canyons, dry washes, sandy deserts, mesas; 300-1200 m; Ariz., Calif., Nev., N.Mex., Tex.; Mexico (Baja California, Chihuahua, Sonora). Baccharis brachyphylla is characterized by the densely branching habit, narrow stems, and small, linear-lanceolate leaves, and hispidulous hairs on stems, leaves, phyllaries, and cypselae.
Plant: Dioecious shrub 30-70 cm; twigs and leaves with gland-tipped hairs, stems erect, much-branched, wand-like Leaves: leaves alternate, cauline, simple, reduced to bracts above, linear, entire; 10-20 mm long, 1-2 mm wide; principal vein 1 INFLORESCENCE: primary inflorescence a head, each resembling a flower; heads in open panicles; involucre funnel- or bell-shaped, of staminate heads 3.8-5.2 mm, of pistillate heads 4.5-6 mm; phyllaries in 4-5 series, lanceolate, glandular-puberulent, acute to long-tapered; receptacle convex, honeycombed, puberulent, chaff 0 Flowers: Staminate flowers (8)12-18(29); corollas 3.3-4.2 mm; pappus 3-4.4 mm; Pistillate flowers 8-18; corollas 2-2.8 mm Fruit: achenes, 2-3 mm, ± cylindric, glandular-puberulent; ribs 5; pappus 4.5-6.5 mm, of many bristles > involucre Misc: Canyon bottoms, dry washes; 300-1200 m.; Jul-Nov