4a. Leaves halberd-shape, the basal lobes directed sidewise =Red Sorrel, Rumex acetosella.= 4b. Leaves arrow-shape, the basal lobes directed backward =Green Sorrel, Rumex acetosa.= 5a. The projecting wings of the fruiting calyx (known as valves) with sharp slender teeth =Bitter Dock, Rumex obtusifolius.= 5b. Valves entire or finely dentate, but without sharp slender teeth --6. 6a. Pedicels straight, thickened toward the end, all regularly deflexed, 3-4 times longer than the fruiting calyx =Swamp Dock, Rumex verticillatus.= 6b. Pedicels slender, flexuous, spreading --7. 7a. Leaves flat or nearly so --8. 7b. Leaves with strongly crisped or wavy-curled margins; plants usually of cultivated grounds or waste places (5-10 dm., summer) --12. 8a. With grain-like tubercles on all 3 valves of the fruit --9. 8b. With grain-like tubercles on only one valve, or entirely lacking --10. 9a. Valves broadly cordate, finely toothed =Water Dock, Rumex brittanica.= 9b. Valves triangular-ovate, entire or nearly so =Dock, Rumex mexicanus.= 10a. Valves oblong =Bloody Dock, Rumex sanguineus.= 10b. Valves broadly heart-shape --11. 11a. Grain-like tubercle less than half as long as the valve =Patience Dock, Rumex patientia.= 11b. Grain-like tubercle more than half as long as the valve =Tall Dock, Rumex altissimus.= 12a. The grain-like tubercle on the valves of the fruit broadly ellipsoid, with rounded apex =Sour Dock, Rumex crispus.= 12b. Tubercle ovoid with tapering apex =Sour Dock, Rumex elongatus.= 13a. Flowers inconspicuous, in small axillary clusters; leaves jointed at the base (Knotweed) --14. 13b. Flowers more or less conspicuous, in obvious spikes or racemes which terminate the stems or branches, or arise from the axils of the upper leaves --18. 14a. Leaves sharply folded lengthwise (1-4 dm. tall) =Knotweed, Polygonum tenue.= 14b. Leaves flat or nearly so --15. 15a. The small sepals pink or white at the margin (stems prostrate or ascending) --16. 15b. Sepals greenish or yellowish throughout (stems erect or ascending) --17. 16a. Leaves thin; common weed of dooryards and gardens =Knotweed, Polygonum aviculare.= 16b. Leaves thick and fleshy; a plant of sandy shores =Knotweed, Polygonum aviculare var. littorale.=