Dimeresia howellii
Gerald D. Carr

Flora of Oregon

Herbs annual, cespitose, often acaulescent; taprooted.

Stems 0 or ? 3 cm, simple or with whorls of several branches, glabrous.

Leaves basal and cauline, crowded, usually whorled below, opposite above, spatulate to lanceolate, ovate, or broadly elliptic, 4–35 mm, margins entire, tips acute to obtuse, surfaces abaxially glabrous or lightly villous, sometimes obscurely punctate-glandular; sessile or petioles 1–12 mm.

Inflorescences 1–many heads in 1–10 dense clusters.

Heads discoid, erect; sessile or peduncles 0–1 mm, surfaces glabrous to woolly-villous.

Involucres cylindric to obconic, 4–6 × 2(4) mm.

Phyllaries 2–3 in 1 equal series, erect, deciduous in fruit, broadly elliptic or ovate, obscurely parallel-veined, tips obtuse, surfaces glabrous.

Receptacles minute; paleae 0.

Florets (1)2–3, corolla tubes 1.5–2 mm, white or purple, lobes 5, spreading, 0.5–2 mm, white or purple at base; stamens partly or wholly exserted; stigmas included.

Fruits cylindric or oblanceolate, tapering to base, flattened, truncate, 2.5–3 mm, black, glabrous, with 14–20 inconspicuous ribs; pappi of basally connate, plumose scales or flattened bristles, deciduous, 3–4 mm, white.

2n=14.

Rocky ridges, hillsides, talus slopes, sagebrush flats. Flowering May–Jul. 700–2800 m. BR, BW, ECas, Owy. CA, ID, NV. Native.

Flora of North America

as described under Dimeresia howellii

Leaf blades (2-)10-30+ mm, initially cobwebby, glabrescent, often gland-dotted. Corollas 5-6 mm. Cypselae 2-3 mm; pappi 3-4 mm (bristles falling together). 2n = 14.Flowering spring-summer. Open gravelly or sandy places, talus slopes screes, serpentine; 1100-2900 m; Calif., Idaho, Nev., Oreg.

Photo images

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Herbarium specimens

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https://intermountainbiota.org/imglib/storage/reno/plantae/00052/52688_tn.jpg
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https://intermountainbiota.org/imglib/storage/reno/plantae/00052/52692_tn.jpg
https://www.pnwherbaria.org/images/thumbnail.php?Image=WTU-V-001121.jpg