Description from Flora of China
Bistorta amplexicaulis (D. Don) Greene; B. petiolata (D. Don) V. Petrov; B. speciosa (Meisner) Greene; Persicaria amplexicaulis (D. Don) Ronse Decraene; Polygonum ambiguum Meisner; P. amplexicaule var. speciosum (Meisner) J. D. Hooker; P. oxyphyllum Wallich ex Meisner; P. petiolatum D. Don; P. speciosum Meisner.
Inflorescence dense. Tepals elliptic, 4-5 × 2-2.5 mm.
One of us (Ohba) notes that Polygonum sinomontanum differs from this variety by its frequently branched stem in the lower part, winged and undulate petioles, and inflorescence usually flowering downward.
This variety is used medicinally.
Shaded grassy places in valleys, mixed forests on mountain slopes; 1000-3300 m. Hubei, Sichuan, Xizang, Yunnan [Bhutan, India, Kashmir, Nepal, Pakistan].