Annuals, 10-150 cm. Leaf blades: bases ± clasping, faces usually both hirtellous to villous and ± gland-ular-viscid; proximal broadly spatulate to oblong, 20-50 × 10-20 mm, obscurely lobed or coarsely toothed; distal oblong to elliptic, 10-20 × 3-10 mm, coarsely toothed from near bases or entire. Heads in racemiform-paniculiform arrays. Involucres 2.5-3+ mm. Receptacles 2-3 mm diam. Pistillate florets 60-100+; corollas: lengths ± ¹ / 2 styles, laminae 0. Disc florets 5-20. Cypselae pale tan, 0.5-1 mm, glabrous or sparsely strigillose (hairs 0.05-0.1 mm), sometimes stipitate- or sessile-glandular; pappi fragile or readily falling, of 10-30 whitish bristles in 1 series, (2.5-)3.5-4 mm. 2n = 18. Flowering year round, mostly fall. Stream banks, roadsides, other disturbed sites, clays or sands, often alkaline soils; -60-1800 m; Ariz., Calif., Colo., Nev., N.Mex., Tex., Utah; Mexico. J. M. Kingsbury (1964) reported Laënnecia coulteri (as Conyza coulteri) to be toxic to livestock.

Plant: Taprooted annual forb to 1 m; herbage sticky glandular Leaves: Taprooted annual forb to 1 m; herbage sticky glandular; leaves mostly alternate, clasping, oblong-lanceolate, 2-15 mm wide, regularly toothed or shallowly lobed Flowers: inflorescence many-flowered elongate panicles; flower heads ~3mm across, discoid; pistillate flowers filiform, in several series along outside of head; hermaphrodite flowers yellow toward center of head; pappus of white capillary bristles. Notes: stems striate References: Veg. & Flora of the Sonoran Desert, ASU specimens