Gumweed

Sclerocarpus gracilis Smith in A. Rees, Cycl. 31: Sclerocarpus no. 2. 1815; Madia gracilis subsp. collina D. D. Keck; M. gracilis subsp. pilosa D. D. Keck

Plants 6–100 cm, self-compatible (heads not showy). Stems prox-imally pilose to hirsute, distally glandular-pubescent, glands yel-lowish, purple, or black, lateral branches seldom surpassing main stems. Leaf blades oblong to linear, 1–10(–15) cm × 1–8(–10) mm. Heads in ± open, paniculiform or racemiform arrays. Involucres depressed-globose to urceolate, 5–10 mm. Phyllaries sometimes hirsute, always finely or coarsely glandular-pubescent, glands yellowish, purple, or black, apices erect or ± reflexed, flat. Paleae mostly persistent, connate ¹/2+ their lengths. Ray florets 3–10; corollas lemon yellow or greenish yellow, laminae 1.5–8 mm. Disc florets 2–16+, bisexual, fertile; corollas 2.5–5 mm, pubescent; anthers ± dark purple. Ray cypselae black, purple, or mottled, dull, compressed, beakless (or nearly so). Disc cypselae similar. 2n = 32, 48.

Flowering Apr–Aug. Open or partially shaded slopes or flats in grasslands, meadows, shrublands, woodlands, and forests, disturbed sites, stream banks, roadsides, coarse to fine textured soils, sometimes serpentine; 0–2500 m; B.C.; Calif., Idaho, Mont., Nev., Oreg., Utah, Wash.; Mexico (Baja California).

Madia gracilis occurs widely in California (except the warm deserts), is scattered across much of Nevada, Oregon, and Washington (outside the driest regions), and extends into southernmost British Columbia, north-western Montana, and northern Utah. Near the coast, M. gracilis sometimes co-occurs with M. sativa; the two species are partially interfertile (M. gracilis tends to flower earlier than M. sativa; J. Clausen 1951). Reported occurrences of M. gracilis in Maine and South America have not been confirmed.