Eriogonum ursinum

S. Watson

Proc. Amer. Acad. Arts 10: 347. 1875.

Endemic
Treatment appears in FNA Volume 5. Treatment on page 358. Mentioned on page 334.

Herbs, spreading, matted, synoecious, 0.5–4 × (1.5–)2–8(–12), thinly tomen-tose to floccose or glabrate. Stems: caudex spreading; aerial flowering stems erect, slender, solid, not fistulose, arising at nodes of caudex branches and at distal nodes of short, non-flowering aerial branches, 0.4–4 dm, thinly tomentose to floccose or glabrate. Leaves in rather compact basal rosettes; petiole 0.1–1.5 cm, tomentose; blade elliptic, 0.7–2(–2.2) × 0.4–1(–1.2) cm, or ovate, 0.8–1.4(–2.5) × 0.5–1.2(–2) cm, densely white- or rufous-tomentose abaxially, thinly tomentose, sparsely floccose, or glabrous and greenish adaxially, margins slightly wavy. Inflorescences compound-umbellate, 1–3(–6) × 1–5 cm, thinly tomentose to glabrate; bracts: proximal 3–8, lanceolate to narrowly elliptic, 0.5–2 × 0.25–1 cm, distal 3, semileaflike, midway along branch, linear to narrowly lanceolate, 0.7–1 × 0.1–0.25 cm, or ± scalelike below involucre, 1–5 mm. Involucres 1 per node, turbinate to turbinate-campanulate, 3.5–8 × 2.5–4 mm, villous; teeth 5–8, erect, 0.5–2 mm. Flowers 5–7 mm at anthesis, 6.5–9 mm in fruit, including 0.5–0.8 mm stipelike base, with perianth cream or rarely yellow, suffused with blush of pinkish red to maroon, glabrous, or flowers 4–6 mm, including 1–1.3 mm stipelike base, with perianth pale yellow or rarely yellow, not suffused with blush of color glabrous; tepals slightly dimorphic or monomorphic, broadly ovate or obovate; stamens exserted, 3–5 mm; filaments pilose proximally. Achenes light brown, (5–)5.5–8 mm or 3–3.5 mm, glabrous except for sparsely pubescent beak.

Discussion

Varieties 2 (2 in the flora).

Selected References

None.

Key

1 Flowers 5-9 mm, perianth cream, rarely yellow; achenes (5-)5.5-8 mm; North Coast Ranges, Siskiyou and Trinity counties Eriogonum ursinum var. erubescens
1 Flowers 4-6 mm, perianth pale yellow or rarely yellow; achenes 3-3.5 mm; n Sierra Nevada, Lassen and Shasta counties to Nevada, Placer, Plumas, and Sierra counties Eriogonum ursinum var. ursinum