| Symbol | Scientific name | Common name/Accepted name (for synonyms) | Family |
| CAST7 | Carex straminiformis Bailey | Shasta sedge | Cyperaceae
|
| CASTB | Carex striata Michx. var. brevis Bailey | Walter's sedge | Cyperaceae
|
| CASTE6 | Carex striata Michx. var. erecta (Dewey) C.F. Reed | Carex angustata | Cyperaceae
|
| CASTS4 | Carex striata Michx. var. striata | Walter's sedge | Cyperaceae
|
| CAST41 | Carex striata Michx. | Walter's sedge | Cyperaceae
|
| CAST17 | Carex striatula Michx. | lined sedge | Cyperaceae
|
| CASTD | Carex stricta Lam. var. decora Bailey | Carex haydenii | Cyperaceae
|
| CASTE4 | Carex stricta Lam. var. elongata (Boeckl.) Gleason | Carex emoryi | Cyperaceae
|
| CASTS | Carex stricta Lam. var. strictior (Dewey) Carey | Carex stricta | Cyperaceae
|
| CAST8 | Carex stricta Lam. | upright sedge | Cyperaceae
|
| CAST23 | Carex strictior Dewey | Carex stricta | Cyperaceae
|
| CAST38 | Carex stygia Holm, non Fries p.p | Carex pluriflora | Cyperaceae
|
| CAST38 | Carex stygia Holm, non Fries p.p | Carex rariflora | Cyperaceae
|
| CAST9 | Carex styloflexa Buckl. | bent sedge | Cyperaceae
|
| CASTN | Carex stylosa C.A. Mey. var. nigritella (Drej.) Fern. | Carex stylosa | Cyperaceae
|
| CASTV | Carex stylosa C.A. Mey. var. virens Bailey | Carex aperta | Cyperaceae
|
| CAST10 | Carex stylosa C.A. Mey. | variegated sedge | Cyperaceae
|
| CASU4 | Carex subbracteata Mackenzie | smallbract sedge | Cyperaceae
|
| CASU5 | Carex suberecta (Olney) Britt. | prairie straw sedge | Cyperaceae
|
| CASU6 | Carex subfusca W. Boott | brown sedge | Cyperaceae
|
| CASU14 | Carex �subimpressa Clokey (pro sp.) | | Cyperaceae
|
| CASU7 | Carex subnigricans Stacey | nearlyblack sedge | Cyperaceae
|
| CASU21 | Carex suborbiculata Mackenzie | Carex nudata | Cyperaceae
|
| CASU8 | Carex subspathacea Wormsk. ex Hornem. | Hoppner's sedge | Cyperaceae
|
| CASU24 | Carex substricta (K�kenth.) Mackenzie | Carex aquatilis var. aquatilis | Cyperaceae
|
| CASU15 | Carex �subviridula Fern. | | Cyperaceae
|
| CASU23 | Carex suksdorfii K�kenth. | Carex aquatilis var. aquatilis | Cyperaceae
|
| CASU16 | Carex �sullivantii Boott | | Cyperaceae
|
| CASUS4 | Carex supina Willd. ex Wahlenb. ssp. spaniocarpa (Steud.) Hult�n | Carex supina var. spaniocarpa | Cyperaceae
|
| CASUS3 | Carex supina Willd. ex Wahlenb. var. spaniocarpa (Steud.) Boivin | weak arctic sedge | Cyperaceae
|
| CASU9 | Carex supina Willd. ex Wahlenb. | weak arctic sedge | Cyperaceae
|
| CASV | Carex svensonis Skottsberg | Carex echinata ssp. echinata | Cyperaceae
|
| CASW | Carex swanii (Fern.) Mackenzie | Swan's sedge | Cyperaceae
|
| CASY | Carex sychnocephala Carey | manyhead sedge | Cyperaceae
|
| CASY3 | Carex sylvatica Huds. | European woodland sedge | Cyperaceae
|
| CASY4 | Carex sylvicola J. Webber & P.W. Ball | Carex radiata | Cyperaceae
|
| CATA | Carex tahoensis Smiley | Tahoe sedge | Cyperaceae
|
| CATE12 | Carex tenax Chapman | wire sedge | Cyperaceae
|
| CATEE | Carex tenera Dewey var. echinodes (Fern.) Wieg. | Carex tenera | Cyperaceae
|
| CATE3 | Carex tenera Dewey | quill sedge | Cyperaceae
|
| CATE4 | Carex teneriformis Mackenzie | Sierra slender sedge | Cyperaceae
|
| CATE5 | Carex tenuiflora Wahlenb. | sparseflower sedge | Cyperaceae
|
| CATEM | Carex tetanica Schkuhr var. meadii (Dewey) Bailey | Carex meadii | Cyperaceae
|
| CATEW | Carex tetanica Schkuhr var. woodii (Dewey) Wood | Carex woodii | Cyperaceae
|
| CATE6 | Carex tetanica Schkuhr | rigid sedge | Cyperaceae
|
| CATE29 | Carex tetrastachya Scheele | Britton's sedge | Cyperaceae
|
| CATE7 | Carex texensis (Torr.) Bailey | Texas sedge | Cyperaceae
|
| CATH6 | Carex thunbergii Steud. | Maui sedge | Cyperaceae
|
| CATH | Carex thurberi Dewey | Thurber's sedge | Cyperaceae
|
| CATI2 | Carex tincta (Fern.) Fern. | tinged sedge | Cyperaceae
|
| CATI5 | Carex tiogana D. Taylor & J. Mastrogiuseppe | Tioga Pass sedge | Cyperaceae
|
| CATO14 | Carex tolmiei Boott | Carex spectabilis | Cyperaceae
|
| CATO17 | Carex tolmiei auct. non Boott | Carex paysonis | Cyperaceae
|
| CATO9 | Carex tompkinsii J.T. Howell | Thompkins' sedge | Cyperaceae
|
| CATOR | Carex tonsa (Fern.) Bickn. var. rugosperma (Mackenzie) Crins | parachute sedge | Cyperaceae
|
| CATOT | Carex tonsa (Fern.) Bickn. var. tonsa | shaved sedge | Cyperaceae
|
| CATO10 | Carex tonsa (Fern.) Bickn. | shaved sedge | Cyperaceae
|
| CATO3 | Carex torreyi Tuckerman | Torrey's sedge | Cyperaceae
|
| CATO4 | Carex torta Boott ex Tuckerman | twisted sedge | Cyperaceae
|
| CATR17 | Carex tracyi auct. non Mackenzie | Carex ovalis | Cyperaceae
|
| CATR6 | Carex triangularis Boeckl. | eastern fox sedge | Cyperaceae
|
| CATRM2 | Carex tribuloides Wahlenb. var. moniliformis (Tuckerman) Britt. | Carex scoparia var. scoparia | Cyperaceae
|
| CATRS2 | Carex tribuloides Wahlenb. var. sangamonensis Clokey | blunt broom sedge | Cyperaceae
|
| CATRT2 | Carex tribuloides Wahlenb. var. tribuloides | blunt broom sedge | Cyperaceae
|
| CATR7 | Carex tribuloides Wahlenb. | blunt broom sedge | Cyperaceae
|
| CATR16 | Carex triceps Mackenzie | Carex hirsutella | Cyperaceae
|
| CATR11 | Carex �trichina Fern. | | Cyperaceae
|
| CATR8 | Carex trichocarpa Muhl. ex Willd. | hairyfruit sedge | Cyperaceae
|
| CATR9 | Carex triquetra Boott | triangularfruit sedge | Cyperaceae
|
| CATRB | Carex trisperma Dewey var. billingsii Knight | Billings' sedge | Cyperaceae
|
| CATRT3 | Carex trisperma Dewey var. trisperma | threeseeded sedge | Cyperaceae
|
| CATR10 | Carex trisperma Dewey | threeseeded sedge | Cyperaceae
|
| CATU2 | Carex tuckermanii Dewey | Tuckerman's sedge | Cyperaceae
|
| CATU3 | Carex tumulicola Mackenzie | splitawn sedge | Cyperaceae
|
| CATU4 | Carex turgescens Torr. | pinebarren sedge | Cyperaceae
|
| CATU9 | Carex turgidula Bailey | Carex aperta | Cyperaceae
|
| CATY | Carex typhina Michx. | cattail sedge | Cyperaceae
|
| CAUB | Carex uberior (C. Mohr) Mackenzie | Carex stipata var. maxima | Cyperaceae
|
| CAUL | Carex ultra Bailey | Cochise sedge | Cyperaceae
|
| CAUMT | Carex umbellata Schkuhr ex Willd. var. tonsa Fern. | Carex tonsa var. tonsa | Cyperaceae
|
| CAUM4 | Carex umbellata Schkuhr ex Willd. | parasol sedge | Cyperaceae
|
| CAUN8 | Carex uncompahgre L. Kelso | Carex bella | Cyperaceae
|
| CAUN3 | Carex unilateralis Mackenzie | lateral sedge | Cyperaceae
|
| CAUR | Carex ursina Dewey | bear sedge | Cyperaceae
|
| CAUT | Carex utriculata Boott | Northwest Territory sedge | Cyperaceae
|
| CAVA2 | Carex vaginata Tausch | sheathed sedge | Cyperaceae
|
| CAVAI | Carex vahlii Schkuhr var. inferalpina Wahlenb. | Carex norvegica ssp. inferalpina | Cyperaceae
|
| CAVAR | Carex vallicola Dewey var. rusbyi (Mackenzie) F.J. Herm. | Rusby's sedge | Cyperaceae
|
| CAVAV | Carex vallicola Dewey var. vallicola | valley sedge | Cyperaceae
|
| CAVA3 | Carex vallicola Dewey | valley sedge | Cyperaceae
|
| CAVAA | Carex varia Muhl. ex Willd. var. australis Bailey | Carex albicans var. australis | Cyperaceae
|
| CAVA5 | Carex varia Muhl. ex Willd., non Host | Carex albicans var. albicans | Cyperaceae
|
| CAVEM | Carex venusta Dewey var. minor Boeckl. | darkgreen sedge | Cyperaceae
|
| CAVEV | Carex venusta Dewey var. venusta | darkgreen sedge | Cyperaceae
|
| CAVE7 | Carex venusta Dewey | darkgreen sedge | Cyperaceae
|
| CAVE14 | Carex venustula Holm | Carex podocarpa | Cyperaceae
|
| CAVE5 | Carex vernacula Bailey | native sedge | Cyperaceae
|
| CAVE8 | Carex verrucosa Muhl. | warty sedge | Cyperaceae
|
| CAVED | Carex vesicaria L. var. distenta Fries | blister sedge | Cyperaceae
|
| CAVEJ | Carex vesicaria L. var. jejuna Fern. | blister sedge | Cyperaceae
|
| CAVEL | Carex vesicaria L. var. laurentiana Fern. | Laurent's sedge | Cyperaceae
|