Eriogonum compositum

Douglas ex Bentham

Edwards’s Bot. Reg. 21: plate 1774. 1835.

Endemic
Treatment appears in FNA Volume 5. Treatment on page 355. Mentioned on page 332.

Herbs, erect, infrequently polygamodioecious, 2–4(–7) × 2–5 dm; floccose or glabrous. Stems: caudex spreading; aerial flowering stems erect, slender or stout, hollow, often slightly fistulose, arising at nodes of caudex branches and at distal nodes of short, nonflowering aerial branches, 1–5 dm, floccose or glabrous. Leaves basal, occasionally in rosettes; petiole 4–10(–15) cm, tomentose; blade lanceolate or ovate to deltoid, (2–)7–25 × (0.7–)1–8 cm, densely white-lanate to tomentose abaxially, less so to glabrate and greenish adaxially, margins entire, plane. Inflorescences umbellate or compound-umbellate, 3–20 × 3–20 cm; branches floccose or glabrous; bracts 3–several, leaflike or semileaflike at proximal nodes, linear to linear-lanceolate, 1–3(–6) cm, scalelike distally, usually 1–5 × 0.5–3 mm. Involucres 1 per node, turbinate-campanulate to campanulate, 6–10 × 4–10 mm, sparsely to densely lanate, weakly glandular-puberulent, or glabrous; teeth (5–)7–10, usually not lobelike, erect to weakly reflexed, 2–4 mm. Flowers 5–6 mm, including 0.7–1.5 mm stipelike base; perianth pale to bright yellow, occasionally ochroleucous, glabrous; tepals monomorphic, oblong to oblong-ovate; stamens slightly exserted, 4–8 mm; filaments pilose proximally. Achenes light brown, 5–6 mm, glabrous except for sparsely pubescent beak.

Discussion

Varieties 3 (3 in the flora).

Eriogonum compositum is one of the more attractive members of the genus and does well in cultivation. The three varieties are only weakly differentiated, and both var. lancifolium and var. leianthum merge with var. compositum. The butterfly Euphilotes enoptes is a pollinator of this species.

The Okanagan-Colville Indians of British Columbia and Washington used plants of Eriogonum compositum as a cold remedy, an antidiarrheal, and a wash for infected cuts. Not surprisingly, children used the hollow, often slightly inflated stems as a toy (N. J. Turner et al. 1980).

Selected References

None.

Key

1 Leaf blades lanceolate; Chelan, Kittitas, Okanogan, and Yakima counties, Washington Eriogonum compositum var. lancifolium
1 Leaf blades ovate to deltoid; widespread > 2
2 Involucres sparsely to densely lanate; n California, wc Idaho, Oregon, and Washington Eriogonum compositum var. compositum
2 Involucres glabrous or weakly glandular-puberulent; wc Idaho, ne Oregon, and e Washington Eriogonum compositum var. leianthum