Plants 3-60 cm (self-incompat-ible); glandular, often not strongly scented, sometimes spice-scented. Stems not purple-streaked (often uniformly dark purple). Leaf blades obovate to linear, 6-100 mm, margins (basal leaves) toothed to lobed. Involucres ± campanulate to hemispheric, 4-11 × 3-11+ mm. Phyllaries 3-14, apices often shorter (sometimes longer) than folded bases. Paleae in 1 series between ray and disc florets. Ray florets 3-14; laminae often white, sometimes yellow or pale yellow, 3-22 mm. Disc florets 17-100+; corollas 3.5-6.5 mm; anthers yellow to brownish. Ray cypselae glabrous. Disc pappi of 10-15 usually white (rarely tawny), linear-attenuate to subulate, ± equal scales 2-5 mm, each proximally plumose and often adaxially woolly. 2n = 16.
Flowering Feb-Jul. Openings in scrub, woodlands, forests, grasslands, and meadows, gravelly or sandy soils, sometimes dunes; 0-2700 m; Ariz., Calif., Idaho, N.Mex., Oreg., Utah, Wash.; Mexico (Baja California).
Layia glandulosa occurs in deserts of western North America, extending to the Pacific coast in central and southern California. As treated here (provisionally) and previously, L. glandulosa corresponds to a paraphyletic group; molecular phylogenetic data have indicated that L. discoidea is most closely related to a subset of lineages in L. glandulosa, including yellow-rayed populations previously recognized as subsp. lutea or var. lutea (B. G. Baldwin, unpubl.). Report of L. glandulosa from British Columbia has not been confirmed.
Duration: Annual
Nativity: Native
Lifeform: Forb/Herb
General: Erect annual, branched with purple streaked stems, 3-60 cm, glandular, sometimes spice scented, moderately hispid throughout.
Leaves: Basal leaves narrowly oblong to linear, 6-100 mm long, margins toothed to lobed on basal leaves, upper leaves smaller and entire.
Flowers: Radiate heads on a slender peduncle 1-15 cm long, usually markedly stipitate-glandular with campanulate to hemispheric involucres, 4-11 mm high by 3-11 mm wide; phyllaries 3-14, acute at apex, hirsute; ray florets 3-14, showy, white or tinged with yellow or pinkish yellow; disc florets 17-100, corollas 3.5-6.5 mm, anthers yellow to brownish.
Fruits: Ray cypselae glabrous; disc cypselae thicker, black, with pappuse of 10-15 usually white, linear-attenuate, equal scales 2-5 mm long, each with a tangle of silky shining wool at base.
Ecology: Found on dry open slopes in both gravelly and sandy soils, rarely in dunes below 5,000 ft (1524 m); flowers March-June.
Notes: The white flowers help to distinguish this species, as does the woolly hairs at the base of the cypselae.
Ethnobotany: The seeds were ground into flour and eaten as mush or porridge.
Etymology: Layia is named for George Tradescant Lay (1799-1845) an American botanist, while glandulosa means provided with glands.
Synonyms: Layia glandulosa subsp. lutea
Editor: SBuckley, 2010
