Polygonum sawatchense subsp. oblivium

Stems green, simple or with few branches from base, 5-15(-25) cm, papillose-scabridulous. Leaves persistent, gradually reduced in size distally; ocrea papillose-scabridulous; blade elliptic to oblong-elliptic, 8-20(-25) × 5-10 mm, margins flat, papillose-denticulate. Inflores-cences mostly axillary, if also terminal then less than 5 cm; cymes 1-3(-4)-flowered. Pedicels 1-3 mm. Flowers: at least some open; perianth 3-4 mm; tube 20-30% of perianth length; tepals greenish white or greenish yellow, sometimes flushed with purple, with white margins, oblong-elliptic; midveins greenish or brown, usually branched at base; stamens 8. Achenes elliptic to elliptic-ovate, 2.6-3.3 mm.

Flowering Jun-Aug. Dry or moist meadows, pastures, sagebrush, and forests, on sandy, gravelly, or rocky substrates; 1000-3500 m; B.C.; Calif., Idaho, Nev., Oreg. Wash.