Description from Flora of China
Amaranthus persicarioides Poiret, Encycl., Suppl. 1: 311. 1810; Acroglochin chenopodioides Schrader; A. obtusifolia Blom; A. persicarioides var. muliensis T. P. Soong; A. persicarioides var. multiflora T. P. Soong.
Plants erect, 30-80 cm tall. Stem usually solitary, ribbed, striate, obliquely branched in upper part. Petiole 2-4 cm; leaf blade ovate to narrowly so, 1.5-7(-8.5) × 0.4-5(-5.5) cm, base cuneate, margin irregularly lobed (lobes acutely serrate), entire on upper leaves, apex acute. Inflorescence borne in axils of almost all leaves, erect or oblique, compoundly dichasiumlike, 0.5-6 cm; ultimate branches needle-like with no flowers. Perianth ca. 1 mm in diam., 5-parted to near base; segments narrowly ovate to oblong, slightly keeled abaxially, margin membranous, apex obtuse or subacute. Stamen usually 1; anthers small, exserted in flower, without an appendage. Pyxidium subglobose, ca. 1.5 mm in diam.; style persistent; pericarp free from testa. Seed ca. 1 mm in diam., rim obtuse. Fl. and fr. Jul-Nov.
Eona Aitken (pers. comm.) adds Bhutan to the general distribution based on a specimen at E collected in 1988.
Forest margins, riversides, open hillsides, fields, roadsides, wastelands. Gansu, Guizhou, Hubei, S Hunan, Shaanxi, Sichuan, Yunnan [Bhutan, India, Kashmir, Nepal, Pakistan].