CYPERACEAE (SEDGE FAMILY) 



9 CLADIUM TWIG-RUSH. (C. mariscoldes.) 



10 SCLfcRIA. 



i a Spikelets in i terminal and usually i or 2 lateral 

 clusters ; the stem rough 



TALL NUT-RUSH. (S. triglomerbta.) 

 b Spikelets in 4-6 separated clusters; the stem smooth 



Low NUT-RUSH. (S. verticill&ta.) 



11 CAREX. 



1 a Plant cultivated for the foliage 



MORROW'S SEDGE. (C. morrowi*) 



b Plants not cultivated for the foliage 2 



2 a Both staminate and pistillate spikes present 3 



b Both staminate and pistillate flowers in the same spike. . 62 



3 a Staminate spikes more than one 4 



b Staminate spikes only one 17 



4 a Perigynia hairy 5 



b Perigynia not hair}- 8 



5 a Pistillate spikes usually about % in. long; staminate 



spikes i or 2, very short stalked 



VELVET SEDGE. (C. <uest\ta.) 

 b Pistillate spikes % in. or more long 6 



6 a Mature perigynia about % in. long, gradually tapering 



into the beak HAIRY-FRUITED SEDGE. (C. trichocdrpa.) 



b Mature perigynia about Vs in. long, abruptly tapering 



into the beak 7 



7 a Leaves infolded; stem smooth beneath the spikes 



SLENDER SEDGE. (C. filiformis.) 

 b Leaves flat; stem usually rough just below the spikes 



WOOLLY SEDGE. (C. lanugindsa.) 



8 a Mature pistillate spikes about 2 in. or more long .... 9 

 b Mature pistillate spikes less than 2 in. long n 



9 a All pistillate spikes long-stalked and drooping; peri- 



gynia nerveless FRINGED SEDGE. (C. crinita.) 



b Only the lower pistillate spikes stalked ; perigynia 



nerved 10 



10 a Perigynia straw-colored, abruptly tapering to apex 



BOTTLE SEDGE. (C. utriculata.) 

 b Perigynia green, gradually tapering to apex 



RIVER-BANK SEDGE. (C. riparia.) 



11 a Mature pistillate spikes about Vz in. or more broad.. 12 

 b Mature pistillate spikes about ^ in. or less broad 15 



12 a 3-8 pistillate spikes clustered at top of stem, i or 2 



lower down; perigynia reflexed at maturity 



RETRORSE SEDGE. (C. retrorsa.) 

 b Pistillate spikes not clustered at top of stem 13 



125 



