Bot. Not. 1899: 16. 1899.
Plants perennial, glabrous or very indistinctly papillose normally only on branches of inflorescences, or on veins of leaf-blades abaxially, with fusiform, vertical rootstock. Stems erect, branched from above middle, 50–120 (–150) cm. Leaves: ocrea deciduous or partially persistent at maturity; blade lanceolate to narrowly lanceolate or lanceolate-linear, normally 15–30 × 1–4 cm, apex acute. Inflorescences terminal, occupying distal 1/2 of stem, normally dense in distal part and interrupted at base, narrowly paniculate, branches usually straight or slightly arcuate. Pedicels articulated in proximal 1/3, filiform, 4–9 mm, articulation distinctly swollen. Flowers 15–25 in whorls, inner tepals orbiculate, ovate-orbiculate, or indistinctly reniform, 3.5–5 (–6) × 3–5 mm, base slightly cordate, margins entire or rarely subentire to very weakly erose, undulate or nearly flat, apex obtuse or rounded, occasionally subacute; tubercles normally absent, sometimes with 1 indistinct tubercle or slightly thickened midvein less than 1–1.3 mm wide, normally less than 2 times as wide as inner tepals. Achenes usually reddish-brown, 2–2.5 × 1–1.5 mm. 2n = 40.
Phenology: Flowering late spring–summer.
Habitat: Ruderal and alluvial habitats, slightly saline soil, waste places, roadsides, shores of rivers and lakes, meadows, cultivated fields
Elevation: 10-1000 m
Introduced; Alta., B.C., Man., Ont., Sask., Yukon, Minn., N.Dak., S.Dak., e Europe, c Asia (Siberia)
Rumex pseudonatronatus often is confused with R. longifolius and R. crispus.
"/2" is not declared as a valid unit of measurement for this property.