Compilation
Rumex stenophyllus

Plants perennial, glabrous or very indistinctly papillose normally only on veins of leaf blades abaxially, with fusiform, vertical rootstock. Stems erect, branched distal to middle, 40–80(–130) cm. Leaves: ocreae usually deciduous, rarely partially persistent at maturity; blade oblong-lanceolate, lanceolate, or narrowly lanceolate, normally 15–25(–30) × 2–7 cm, base cuneate or truncate, margins entire or irregularly denticulate, usually crisped and undulate, or, occasionally, flat, apex acute or subobtuse. Inflorescences terminal, occupying distal 1/2 of stem, dense or interrupted at base, narrowly paniculate, branches usually straight or occasionally arcuate. Pedicels articulated in proximal 1/3, filiform, 3–8 mm, articulation distinctly swollen. Flowers 20–25 in whorls; inner tepals orbiculate-ovate or occasionally ovate-deltoid, 3.5–5 × 3–5 mm, base truncate or slightly cordate, margins denticulate, apex acute or subacute, teeth 4–10 at each side, 0.2–1.5 mm; tubercles normally 3, equal or subequal, less than 2 times as wide as inner tepals. Achenes usually reddish brown or dark brown, 2–2.5(–3) × 1–1.5 mm. 2n = 60.