Rumex L. >
Leaf bases cordate, cuneate or rounded. Inner perianth segments leathery, often toothed, not inflated Rumex
Inner perianth segments with long teeth, with or without a tubercle
Flower clusters without floral leaves, except the lowest ones
Flower clusters close together, many-flowered, without floral leaves or leafy only near the base of the long racemes. Perianth valves ovate-triangular, 4–5 mm long, obtuse, with c. 3 teeth on each side below the middle; only one of the valves with a large tubercle. Stems erect, stout. Basal leaves large, crenulate, cordate. Widespread. Damp places. Introduced from Europe and Asia. Broad-leaf Dock Rumex obtusifoliusobtusifolius