Modoc County knotweed

Polygonum esotericum L. C. Wheeler, Rhodora 40: 310, fig. 1. 1938

Stems 5-12 cm. Inflorescences con-tinuous from bases of branches or stems, narrowly cylindric, 2-10 × 5-7 mm; bracts appressed, elliptic-lanceolate, 4-8 mm, rigid, margins flat, green, if white then scarious portion 0.1-0.2 mm wide; lateral and midveins prominent adaxially. Flowers: perianth 2.1-2.9 mm; tube 29-40% of perianth length; tepals white or pink; perianth tube and base of tepals smooth; stamens 5-8. Achenes dark brown, lanceolate, 2-2.5 mm, reticulately ridged to almost smooth, dull.

Flowering Jun-Aug. Vernal pools, seasonally wet places, desert scrub, pinyon and juniper woodlands; 1400-1600 m; Calif., Oreg.