R. Patiéntia, L. (Patience Dock.) A very tall species, with ovate-oblong and lanceolate leaves (broadest above the base), those from the root 2–3° long, and one of the heart-shaped nearly or quite entire valves (3´´ broad) bearing a small grain, or its midrib thickened at base.—N. Eng and N. Y. (Adv. from Eu.)
1. R. venòsus, Pursh. Stems from running rootstocks, erect (1° high or less), with conspicuous dilated stipules; leaves on short but rather slender petioles, ovate or oblong to lanceolate (3–6´; long), acute or acuminate, only the lowest obtuse at base; panicle nearly sessile, short, dense in fruit; valves entire, glandless, broadly cordate with a deep sinus, 9–12´´ in diameter, bright rose-color.—Sask. to central Mo. and Kan., and westward.
[+][+] Valves smaller, one or more of them conspicuously grain-bearing.
[++] Indigenous; leaves not wavy, none heart-shaped, except the lowest of n. 5.
2. R. Británnica, L. (Great Water-Dock.) Tall and stout (5–6° high); leaves oblong-lanceolate, rather acute at both ends, transversely veined, and with obscurely erose-crenulate margins (the lowest, including the petiole, 1–2° long, the middle rarely truncate or obscurely cordate at base); racemes upright in a large compound panicle, nearly leafless; whorls crowded; pedicels capillary, nodding, about twice the length of the fruiting calyx; the valves orbicular or round-ovate, very obtuse, obscurely heart-shaped at base, finely reticulated, entire or repand-denticulate (2–3´´ broad), all grain-bearing. (R. orbiculatus, Gray.)—Wet places, N. Eng. to N. J., west to Minn, and Kan.
3. R. altíssimus, Wood. (Pale Dock.) Rather tall (2–6° high); leaves ovate- or oblong-lanceolate, acute, pale, thickish, obscurely veiny (the cauline 3–6´ long, contracted at base into a short petiole); racemes spike-like and panicled, nearly leafless; whorls crowded; pedicels nodding, shorter than the fruiting calyx; valves broadly ovate or obscurely heart-shaped, obtuse or acutish, entire, loosely reticulated (about 2´´ broad), one with a conspicuous grain, the others with a thickened midrib or naked. (R. Britannica, Gray; not L.)—Moist grounds, N. Y. and N. J. to Minn., and Kan.
4. R. salicifòlius, Weinmann. (White Dock.) Rather low (1–3° high); root white, leaves narrowly or linear-lanceolate, or the lowest oblong; whorls much crowded; pedicels much shorter than the fruiting calyx; valves deltoid-ovate, obtusish or acutish (about 1½´´ long), one, two or sometimes all with a conspicuous often very large grain; otherwise nearly as n. 3.—Salt marshes, from Newf. to N. Eng., about the Great Lakes, and far westward.
5. R. verticillàtus, L. (Swamp Dock.) Rather tall (3–5° high); leaves lanceolate or oblong-lanceolate, rather obtuse, thickish, pale-green, the lowest often heart-shaped at base; racemes nearly leafless, elongated, loose, the whorls crowded or the lower ones distant; fruit-bearing pedicels slender, club-shaped, abruptly reflexed, 3–4 times longer than the fruiting calyx; valves dilated-rhomboid, obtusely somewhat pointed, strongly rugose-reticulated, each bearing a very large grain.—Wet swamps, common.
[++][++] Naturalized European weeds; lower leaves mostly heart-shaped at base.
R. críspus, L. (Curled Dock.) Smooth (3–4° high); leaves with strongly wavy-curled margins, lanceolate, acute, the lower truncate or scarcely heart-shaped at base; whorls crowded in prolonged wand-like racemes, leafless above; valves round-heart-shaped, obscurely denticulate or entire, mostly all grain-bearing.—In cultivated and waste ground, very common. A hybrid of this with the next is reported from Mass., N. Y., and Md.