4.
Madia exigua
(Smith) A. Gray, Proc. Amer. Acad. Arts. 8: 391. 1872.
Sclerocarpus exigua
Smith in A. Rees, Cycl. 31: Sclerocarpus no. 3. 1815
Plants
1—30(—50) cm, self-compatible (heads not showy).
Stems
hirsute and glandular-pubescent, glands yellowish or purple, lateral branches seldom surpassing main stems.
Leaf blades
linear, 0.2—4 cm × 0.5—2 mm.
Heads
in open, corymbiform arrays (peduncles ± filiform).
Involucres
depressed-globose, 2.5—5 mm.
Phyllaries
± hirsute and glandular-pubescent as well, glands golden yellow, apices ± erect, sulcate.
Paleae
mostly persistent, connate
1
/2+ their lengths.
Ray florets
1—8; corollas pale yellow, laminae 0.7—1 mm.
Disc florets
1(—2), bisexual, fertile; corollas 1—1.8 mm, glabrous; anthers yellow to brownish.
Ray cypselae
black or brown, dull, compressed (strongly arcuate), beaked (beaks adaxially offset, curved).
Disc cypselae
obovoid, weakly compressed.
2
n
= 32.
Flowering Apr—Jul. Openings in grasslands, meadows, shrublands, woodlands, and forests, disturbed sites, often sandy, gravelly, or clayey soils, sometimes serpentine; 30—2500 m; B.C.; Calif., Idaho, Mont., Nev., Oreg., Wash.; Mexico (Baja California).
Madia exigua
occurs in seasonally dry situations in much of western North America outside the warm deserts. Morphologically,
M. exigua
is somewhat similar to
Hemizonella minima
, which (unlike
M. exigua
) has subumbellate arrays of heads and obcompressed, sparsely hairy ray cypselae.
