The plant may cause dermatitis similar to that caused by poison ivy when 

 handled by some individuals. At one time the root was used as medicine under 

 the name "yellow dock." 



11. Rumex conglomeratus Murr. 



Rather similar to R. crispus; lower leaves cordate at base, flat; branches of the 

 panicle divergent, whorls of inflorescence each with a bracteal leaf, remote; 

 pedicels usually not longer than the fruit; valves entire-margined, 2.5-3 mm. long, 

 each with a large grain dorsally. 



Floodplain woods, ditches, stream banks and in wet sandy spots, rare in e. 

 Tex. and perhaps elsewhere, and Ariz. (Maricopa, Santa Cruz and Pinal cos.), 

 spring; nat. of Eur., now widely adv. 



12. Rumex stenophyllus Ledeb. 



Perennial; stems erect or ascending, 6-12 dm. tall, branching from the base; 

 leaves petioled, papery, light-green, glabrous and smooth; lower leaves broadly 

 linear-lanceolate, flat and marginally crisped, 3-4 dm. long, 4-10 cm. wide, nar- 

 rowed at both ends, the cauline leaves and those subtending branches of the inflo- 

 rescence similar to basal leaves but smaller; flowers in approximate glomerules on 

 branches of a panicle; pedicels 4-7 mm. long, articulate at or below the middle; 

 valves broadly triangular with a truncate base, narrowly obtuse to acute at apex, 

 the margins spinose-dentate, all the valves with a similar prominent callous grain; 

 achene nut-brown, about 2.5 mm. long. R. alluvius Gates & McGregor. 



In marshy areas about lakes and in alluvial soils along streams, Okla. (Alfalfa 

 Co.), May-Aug.; Man., s. to Mo. and Okla.; nat. of Euras. 



As Steyermark has noted, plants of this species resemble a hybrid between 

 R. crispus and R. obtusifoUus. The fully developed grain on each of the 3 toothed 

 valves, however, readily separate it from the above species. 



13. Rumex obtusifolius L. Bitter dock. 



Perennial; stems from a stout taproot, simple or sparingly branched at base, 

 tall, slender, 6-12 dm. tall; lower leaves ovate-oblong to broadly oblong-lanceolate, 

 10-35 mm. long, somewhat undulate, margins slightly crisped, usually deeply 

 cordate at base, somewhat papillate on lower surface, glabrous, dark green, on 

 long petioles; panicle strict, leafless or with a few leaves at base, open, the glo- 

 merules not crowded, the lower ones remote; pedicels slender, 1 to 2.5 times as 

 long as the mature perianth, articulate near base; flowers perfect; valves deltoid- 

 ovate, 4-6 mm, long, with 3 or 4 pronounced spinose or subulate teeth on each 

 margin, 1 valve with a small callous grain, sometimes the other 2 with very small 

 grains; achene 2 mm. long, reddish-brown, shining. 



Wet grounds and springy stream banks, marshy areas and floodplains, in Okla. 

 (Cherokee, Pottawattomie and Kiowa cos.), the Tex Panhandle (Castro, Hale and 

 Randall cos.), N. M. (Sierra, Valencia and Union cos.) and Ariz. (Cochise and 

 Pima COS.), spring-summer; nat. of Eur., now widely distributed. 



14. Rumex pulcher L. Fiddle dock. Fig. 401. 



Perennial herb; stems erect, 5-8 dm. tall; lower leaves small, long-petioled, 

 3-15 cm. long, cordate at base, somewhat crisp marginally, often pubescent 

 beneath; branches of the panicle very divergent, often intricately enmeshed at 

 fruiting time; some of the whorls with bracteal leaves, all remote; pedicels thick, 

 not longer than the fruit, jointed in the middle; valves denticulate-margined, 3-6 

 mm. long, 2.5-4.5 mm. broad, usually all dorsomedially with a grain but the 

 grains of disparate size even in the same flower; achenes 3-4 mm. long. 



805 



