Eriogonum umbellatum var. haussknechtii
Contr. W. Bot. 11: 6. 1903.
Herbs, typically prostrate, sprawling mats, 0.5–1.5 × 1–4 dm. Aerial flowering stems spreading to erect, 0.3–0.6(–1.5) dm, thinly tomentose, without one or more leaflike bracts ca. midlength. Leaves typically in tight rosettes; blade usually broadly elliptic, 0.5–1.5(–2.5) × 0.5–1.2(–1.5) cm, tannish-tomentose abaxially, thinly tomentose or glabrous and olive green adaxially, margins plane. Inflorescences compact-umbellate; branches 0.1–1.5(–2) cm, thinly tomentose, without a whorl of bracts ca. midlength; involucral tubes 1.5–3.5 mm, lobes 1–4 mm. Flowers 2–6 mm; perianth bright yellow.
Phenology: Flowering Jun–Sep.
Habitat: Volcanic, sandy to gravelly slopes and ridges, mixed grassland and sagebrush communities, montane to subalpine conifer woodlands
Elevation: 1000-2500(-3100) m
Discussion
Variety haussknechtii, as here circumscribed, is a high-elevation taxon found mainly on volcanic peaks in north-central Oregon (Benton, Clackamas, Hood River, and Wasco counties) and south-central Washington (Kittitas and Yakima counties). It is common on Mt. Hood and Mt. Adams. It typically grows with E. marifolium, and mixed collections often are found in herbaria; the two taxa have in common a distinctive olive green color of the adaxial leaf surfaces. Haussknecht’s sulphur flower is not always clearly distinct from var. modocense. It is occasionally seen in cultivation, especially in European gardens.
Selected References
None.