Wet meadows and thickets, in mud on edge of ponds and lakes, and in 

 seepage areas, in N. M. (Taos Co.) and Ariz. (Navajo, Coconino and Pima 

 COS.); Sask. to Alas., s. to N.M., Ariz, and Calif. 



20. Carex tribuloides Wahl. Fig. 261. 



Tufted perennial; culms 3-8 dm. long, 1-2 mm. thick, basally slightly arcuate- 

 ascending, mostly ascending, apically strongly angled; sheaths short, the venters 

 mostly veiny except for the hyaline area near the orifice; blades (1-) 2.5-5 mm. 

 broad, shorter than the culms and at least the lower ones often relatively stiff 

 and diverging from the culm at an angle of 10-30° (-50°); inflorescence elongate, 

 capitate or shortly subspicate. 25-50 mm. long, 9-15 mm. thick, of 5 to 15 

 closely set sessile burlike obovoid to oblong ascending gynecandrous spikes 7-10 

 mm. long and 3-5 mm. thick; bracts absent except occasionally a small setaceous 

 one at the base of the lowest spike; scales half to two thirds as long as their 

 perigynia; perigynia 50 to 80 per spike, much-flattened and scalelike, distended 

 only over the achene, winged, 3.5-5.2 mm. long (including the bidentate beak 

 which is about 1 mm. long), 1-1.5 mm. broad including the wings (broadest near 

 the middle, i.e., in the upper half of the "body"), stramineous-brown, ventrally 

 veiny, stiffly ascending and apically not appressed nor incurved; achene lenticular, 

 about 1.5 mm. long, 0.7 mm. wide. 



In swampy or low wet meadows and woods of alluvial soils, in mud on edge 

 of ponds, lakes and streams, in Okla. (McCurtain and Alfalfa cos.) and s.e. 

 Tex. (Jefferson, Panola, Gregg, Rusk, Sabine and Montgomery cos.), May; e. 

 temp. N.A. w. to Minn., Mo., Okla. and Tex. 



21. Carex microptera Mack. 



Very densely cespitose from short stout rootstocks; culms 3-10 dm. high, 2.5-4 

 mm. thick at the base, conspicuously striate, sharply triangular above and 

 roughened below the head, much-exceeding the leaves; leaves 3 to 5 to a culm, 

 on the lower third, flat, firm, 2-6 mm. wide; sheaths tight, white-hyaline ventrally; 

 spikes 5 to 20, gynecandrous, distinguishable but densely aggregated into an 

 ovoid or suborbicular, truncate-based head, 12-18 (-25) mm. long, 10-18 mm. 

 wide; lowest bract short-awned; scales ovate-lanceolate, acute, dull-brown, with 

 faint lighter midrib, narrower and shorter than the perigynia; perigynia thin 

 and flattened except where distended by the achene, lanceolate-ovate to lanceo- 

 late, 3.4-5 mm. long, 1-2 mm. wide, spreading-ascending, light-green to light- 

 brown, lightly several-nerved on both surfaces, very narrowly wing-margined 

 to the round-tapering base, serrulate to the middle, tapering into a terete serrulate 

 (smooth at the tip) bidentate beak one-third to one-half the length of the body; 

 achenes lenticular, broadly obovoid, to 1.5 mm. long, about 1 mm. wide; anthers 

 long-persistent, linear-oblong, spinulose apiculate, 1.3-2 mm. long. C. festivella 

 Mack. 



Moist or wet places, in N.M. (Taos, Grant, San Miguel, Catron, Rio Arriba 

 and Sandoval cos.) and Ariz. (Coconino, Pima and Graham cos.); B.C. to Sask. 

 and Man., s. to Calif., N.M., Ariz, and in the Black Hills of S.D. 



22. Carex scoparia Schkuhr. 



Densely cespitose from short fibrillose rootstocks; culms 1.5-10 dm. high, 

 usually much-exceeding the leaves, sharply triangular, the angles very rough 

 below the inflorescence; leaves 2 to 6, on the lower half, flat or canaliculate, 1-3 

 mm. wide, yellowish-green; spikes 3 to 12, distinct, aggregated into an oblong 

 to linear-oblong or globose head (or sometimes a moniliform flexuous inflores- 

 cence), gynecandrous, straw-colored, the numerous erect-ascending perigynia 

 with appressed-erect beaks; scales ovate to oblong-ovate, dull, light-brownish 

 with green center and narrow white-hyaline margins, nearly as wide as the 



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