Amer. J. Bot. 21: 580. 1934.
Annuals, mostly 10–40(–50) cm; taprooted. Stems erect, sparsely hispido-pilose (hairs spreading, straight, 0.6–2 mm), densely stipitate-glandular. Leaves basal (persistent) and cauline; basal and proximal cauline blades obovate-spatulate, 50–100(–150) × 4–25 mm, cauline gradually reduced (lobing distally), margins pinnatifid or bipinnatifid with (1–)2–4 pairs of rounded to acute lobes, faces sparsely hispido-pilose, stipitate-glandular. Heads 1–5 (peduncles long, ebracteate). Involucres 3–4 × 6–10 mm. Phyllaries in 2–3 series (sometimes basally connate, broad, thin) sparsely hispido-pilose, stipitate glandular. Ray florets 85–110; corollas white, drying dark blue, 6–9 mm, laminae not coiling or reflexing. Disc corollas 1.8–2.9 mm. Cypselae 1.2–1.4 mm, 2-nerved, faces sparsely strigose; pappi: outer of scales (sometimes connate, forming crowns), inner of 11–12 bristles.
Phenology: Flowering (Jan–)Feb–May(–Oct).
Habitat: Stream banks, sandy lake shores, dry washes, desert or riparian scrub, sometime with creosote bush
Elevation: 300–1200 m
Ariz., Calif., Nev., Mexico (Sonora).
Erigeron lobatus is characterized by persistent basal and proximal cauline leaves with rounded to acute lobes, vestiture of stipitate glands and sparse, spreading, hispido-pilose hairs, heads on relatively long, ebracteate peduncles, and broad, thin phyllaries. Erigeron divergens often is similar; its glandularity is not stipitate and its nonglandular hairs are shorter and denser.