Phytologia 23: 163. 1972.
Subshrubs, spreading to some-what sprawling, not scapose, (1.5–)2–4 × 2–5 dm, glabrous, grayish. Stems decumbent to spreading, without persistent leaf bases, up to 1/4 height of plant; caudex stems absent or slightly spreading in moving sand; aerial flowering stems spreading, slender, solid, not fistulose, 0.5–1.5 dm, glabrous. Leaves basal or sheathing up proximal 1/4 of flowering stems, 1 per node; petiole 0.1–0.5(–1) cm, tomentose to floccose; blade broadly elliptic, 1–2(–2.5) × 0.8–1.7 cm, densely white-tomentose abaxially, less so to subglabrous and green adaxially, margins plane. Inflorescences cymose, open, 5–20 × 5–20 cm; branches dichotomous, glabrous; bracts 3, scalelike, triangular, 1–2.5 mm. Peduncles absent or erect, restricted to proximal nodes, (0.2–)0.5–1(–1.5) cm, glabrous. Involucres 1 per node, turbinate, (2.5–)3–3.5 × 2–2.5 mm, glabrous; teeth 5, erect, 0.4–0.8 mm. Flowers 2–3 mm; perianth white, glabrous; tepals connate proximal 1/4, essentially monomorphic, narrowly obovate; stamens slightly exserted, 2.5–3.5 mm; filaments puberulent proximally. Achenes light brown, 3–3.5 mm, glabrous except for distinctly papillate beak.
Phenology: Flowering Jun–Sep.
Habitat: Sandy flats and washes, mixed grassland and sagebrush communities, pinyon-juniper woodlands
Elevation: 1600-1900 m
Of conservation concern.
Eriogonum ammophilum is known only from a few, scattered locations in Millard County. It is considered to be a “sensitive” species by the Bureau of Land Management.