Polygonum sawatchense subsp. sawatchense
Stems green to brownish, usually branched from base, 4–50 cm, glabrous. Leaves basal leaves caducous or persistent, distal leaves abruptly reduced to bracts, rarely much longer than flowers; ocrea glabrous; blade linear-lanceolate to narrowly oblong or oblanceolate, 15–45 × 2–8(–12) mm, margins usually revolute, smooth. Inflorescences axillary or axillary and terminal, long, open, racemes, 5–15 cm; cymes (1–)2–4-flowered. Pedicels 1–4 mm. Flowers closed; perianth (2.5–)3–3.5 mm; tube 25–40% of perianth length; tepals greenish or reddish with white or pink margins, oblong; midveins greenish or brown, unbranched or with few branches at base; stamens 3–8. Achenes ovate or elliptic, 2.5–3 mm.
Phenology: Flowering Jun–Aug.
Habitat: Dry meadows, pastures, sagebrush and forests on sandy, gravelly, or rocky substrates
Elevation: 800-3500 m
Alta., Sask., Ariz., Calif., Colo., Idaho, Mont., Nebr., Nev., N.Mex., N.Dak., S.Dak., Utah, Wash., Wyo.