| Cabomba caroliniana Gray | map | |
| Cakile edentula (Bigelow) Hook | map | |
| Cakile harperi Small | map | images (1) (2) (3) (4) |
| Calamagrostis coarctata (Torr.) Eat. | map | |
| Calamintha georgiana (Harper) Shinners | map | images (1) (2) (3) |
| Calamovilfa brevipilis (Torr.) Scribn. | map | |
| Callicarpa americana L. | map | images (1) (2) (3) |
| Callicarpa dichotoma (Lour.) K. Koch | map | |
| Callitriche heterophylla Pursh | map | |
| Callitriche peploides Nutt. | map | |
| Callitriche terrestris Raf. | map | |
| Calopogon barbatus (Walt.) Ames | map | |
| Calopogon multiflorus Lindley | map | |
| Calopogon pallidus Chapman | map | |
| Calopogon tuberosus (L.) B.S.P. | map | images (1) (2) (3) |
| Calycanthus floridus L. var. floridus | map | images (1) (2) (3) |
| Calycanthus floridus L. var. glaucus (Willd.) Torr. & Gray | map | |
| Calystegia catesbiana Pursh ssp. sericata (House) Brumitt | map | |
| Calystegia sepium (L.) R. Br. | map | images (1) (2) |
| Calystegia spithamaea (L.) Pursh | map | |
| Camassia scilloides (Raf.) Cory | map | |
| Camelina microcarpa DC. | map | |
| Campanula aparinoides Pursh | map | |
| Campanula divaricata Michx. | map | images (1) (2) (3) |
| Campanulastrum americanum (L.) Small | map | |
| Campsis radicans (L.) Seem. ex Bureau | map | images (1) (2) (3) (4) |
| Canna flaccida Salisb. | map | |
| Canna x generalis Bailey | map | |
| Cannabis sativa L. | map | |
| Capsella bursa-pastoris (L.) Medik. | map | images (1) (2) |
| Cardamine angustata Hook. | map | images (1) (2) |
| Cardamine bulbosa (Schreb. ex Muhl.) B.S.P. | map | |
| Cardamine concatenata (Michx.) Sudw. | map | |
| Cardamine diphylla (Michx.) Wood | map | |
| Cardamine flagellifera O.E. Schulz | map | |
| Cardamine hirsuta L. | map | images (1) (2) (3) |
| Cardamine parviflora L. var. arenicola (Britt.) O.E. Schulz | map | |
| Cardamine pensylvanica Muhl. ex Willd. | map | images (1) (2) (3) |
| Cardiospermum halicacabum L. | map | |
| Carduus nutans L. | map | |
| Carex abscondita Mackenzie | map | |
| Carex aestivalis M.A. Curtis ex Gray | map | |
| Carex alata Torr. | map | |
| Carex albicans Willd. ex Spreng. | map | |
| Carex albolutescens Schwein. | map | |
| Carex albursina Sheldon | map | |
| Carex amphibola Steud. | map | |
| Carex amplisquama F.J. Herm. | map | |
| Carex annectens (Bickn.) Bickn. | map | |
| Carex appalachica J. Webber & P.W. Ball | map | |
| Carex atlantica ssp. atlantica | map | |
| Carex atlantica ssp. capillacea (Bailey) Reznicek | map | |
| Carex austrocaroliniana Bailey | map | |
| Carex barrattii Schwein. & Torr. | map | |
| Carex basiantha Steudel | map | |
| Carex bicknellii Britt. | map | |
| Carex biltmoreana Mackenzie | map | |
| Carex blanda Dewey | map | |
| Carex bromoides Schkuhr ex Willd. var. bromoides | map | |
| Carex bromoides Schkuhr ex Willd. var. montana Naczi | map | |
| Carex brunnescens (Pers.) Poir. | map | |
| Carex bullata Schkuhr ex Willd. | map | |
| Carex buxbaumii Wahlenb. | map | |
| Carex caroliniana Schwein. | map | |
| Carex cephalophora Muhl. ex Willd. | map | |
| Carex chapmanii Steud. | map | |
| Carex cherokeensis Schwein. | map | |
| Carex collinsii Nutt. | map | |
| Carex communis Bailey | map | |
| Carex comosa Boott | map | |
| Carex complanata Torr. & Hook. | map | |
| Carex crebriflora Wieg. | map | |
| Carex crinita Lam. | map | |
| Carex crus-corvi Shuttlw. ex Kunze | map | |
| Carex dasycarpa Muhl. | map | |
| Carex debilis Michx. var. debilis | map | |
| Carex debilis Michx. var. pubera Gray | map | |
| Carex debilis Michx. var. rudgei Bailey | map | |
| Carex decomposita Muhl. | map | |
| Carex digitalis Willd. | map | |
| Carex eburnea Boott | map | |
| Carex elliottii Schwein & Torr | map | |
| Carex emmonsii Dewey ex Torr. | map | |
| Carex festucacea Schkuhr. ex Willd. | map | images (1) (2) |
| Carex flaccosperma Dewey | map | |
| Carex floridana Schwein. | map | |
| Carex folliculata L. | map | |
| Carex frankii Kunth | map | |
| Carex gigantea Rudge | map | images (1) |
| Carex glaucescens Ell. | map | images (1) |
| Carex gracilescens Steud. | map | |
| Carex gracillima Schwein. | map | |
| Carex granularis Muhl. ex Willd. | map | |
| Carex gravida var. lunelliana (Mackenzie) F.J. Herm. | map | |
| Carex grayi Carey | map | |
| Carex grisea Wahlenb. | map | |
| Carex gynandra Schwein. | map | |
| Carex hyalinolepis Steud. | map | |
| Carex intumescens Rudge | map | |
| Carex jamesii Schwein. | map | |
| Carex joorii Bailey | map | |
| Carex laevivaginata (Kukenth.) Mackenzie | map | |
| Carex laxiculmis Schwein. | map | |
| Carex laxiflora Lam. var. laxiflora | map | |
| Carex laxiflora Lam. var. serrulata F.J. Herm. | map | |
| Carex leavenworthii Dewey | map | |
| Carex leptalea Wahlenb. | map | |
| Carex lonchocarpa Willd. | map | |
| Carex longii Mackenzie | map | |
| Carex louisianica Bailey | map | |
| Carex lucorum Willd. ex Link var. austrolucorum J. Rettig | map | |
| Carex lupuliformis Sartwell ex Dewey | map | |
| Carex lupulina Muhl. ex Willd. | map | |
| Carex lurida Wahlenb. | map | |
| Carex manhartii Bryson | map | |
| Carex mesochorea Mackenzie | map | |
| Carex mitchelliana M.A. Curtis | map | |
| Carex muehlenbergii Schkuhr ex Willd. | map | |
| Carex nigromarginata Schwein. | map | |
| Carex normalis Mackenzie | map | |
| Carex oligocarpa Schkuhr ex Willd. | map | |
| Carex oxylepis Torr. & Hook. | map | |
| Carex pedunculata Muhl. ex Willd. | map | |
| Carex pensylvanica Lam. | map | |
| Carex physorhyncha Liebm. ex Steud. | map | |
| Carex plantaginea Lam. | map | |
| Carex prasina Wahlenb. | map | |
| Carex projecta Mackenzie | map | |
| Carex radfordii Gaddy | map | |
| Carex radiata (Wahlenb.) Sm. | map | |
| Carex reniformis (Bailey) Small | map | |
| Carex retroflexa Muhl. ex Willd. | map | |
| Carex rosea Schkuhr ex Willd. | map | |
| Carex rugosperma Mackenzie | map | |
| Carex ruthii Mackenzie | map | |
| Carex scabrata Schwein. | map | |
| Carex scoparia Schkuhr ex Willd. | map | |
| Carex seorsa Howe | map | |
| Carex socialis Mohlenbrock & Schwegm. | map | |
| Carex sparganioides Muhl. ex Willd. | map | |
| Carex squarrosa L. | map | |
| Carex stipata Muhl. ex Willd. var. maxima Chapman | map | |
| Carex stipata Muhl. ex Willd. var. stipata | map | |
| Carex striata Michx. | map | images (1) (2) |
| Carex striatula Michx. | map | |
| Carex styloflexa Buckl. | map | |
| Carex swanii (Fern.) Mackanzie | map | |
| Carex tenax Chapman | map | images (1) |
| Carex tenera Dewey | map | |
| Carex texensis (Torr.) Bailey | map | |
| Carex tonsa (Fern.) Bickn. | map | |
| Carex torta Boott ex Tuckerman | map | |
| Carex triangularis Boeckl. | map | |
| Carex tribuloides Wahlenb. | map | |
| Carex turgescens Torr. | map | |
| Carex typhina Michx. | map | |
| Carex umbellata Schkuhr ex Willd. | map | |
| Carex venusta Dewey | map | |
| Carex verrucosa Muhl. | map | |
| Carex virescens Muhl. ex Willd. | map | |
| Carex vulpinoidea Michx. | map | |
| Carex willdenowii Schkuhr ex Willd. var. megarrhyncha F.J. Herm. | map | |
| Carex willdenowii Schkuhr ex Willd. var. willdenowii | map | |
| Carex woodii Dewey | map | |
| Carphephorus bellidifolius (Michx.) Torr. & Gray | map | images (1) (2) (3) (4) |
| Carphephorus corymbosus (Nutt.) Torr. & Gray | map | |
| Carphephorus odoratissimus (J.F. Gmel.) Herbert | map | images (1) (2) (3) |
| Carphephorus paniculatus (J.F. Gmel.) Herbert | map | images (1) (2) (3) |
| Carphephorus tomentosus (Michx.) Torr. & Gray | map | |
| Carpinus caroliniana Walt. | map | images (1) (2) (3) (4) |
| Carya alba (Michx.) Nutt. ex Ell. | map | images (1) |
| Carya aquatica (Michx. f.) Nutt. | map | |
| Carya carolinae-septentrionalis (Ashe) Engel. & Graebn. | map | |
| Carya cordiformis (Wangenh.) K. Koch | map | |
| Carya glabra (P. Mill.) Sweet | map | |
| Carya illinoinensis (Wangenh.) K. Koch | map | |
| Carya laciniosa (Michx. f.) G. Don | map | |
| Carya myristiciformis (Michx. f.) Nutt. | map | |
| Carya ovata (P. Mill.) K. Koch | map | images (1) |
| Carya pallida (Ashe) Engl.& Graebn. | map | |
| Carya x Lecontei Little | map | |
| Castanea dentata (Marsh.) Borkh. | map | |
| Castanea pumila (L.) P. Mill. | map | images (1) (2) (3) |
| Castilleja coccinea (L.) Spreng. | map | |
| Catalpa bignonioides Walt. | map | |
| Catalpa speciosa (Warder) Warder ex Engelm. | map | images (1) (2) |
| Catharanthus roseus (L.) G. Don | map | |
| Caulophyllum thalictroides (L.) Michx. | map | images (1) (2) |
| Cayaponia quinqueloba (Raf.) Shinners | map | |
| Ceanothus americanus L. | map | images (1) (2) (3) |
| Cedrus deodara (Roxb. ex D. Don) G. Don | map | |
| Celastrus orbiculatus Thunb. | map | |
| Celastrus scandens L. | map | |
| Celtis laevigata Willd. | map | images (1) (2) (3) (4) |
| Celtis occidentalis L. | map | |
| Celtis tenuifolia Nutt. | map | |
| Cenchrus carolinianus Walt. | map | |
| Cenchrus echinatus L. | map | images (1) (2) |
| Cenchrus longispinus (Hack.) Fern. | map | images (1) (2) |
| Cenchrus myosuroides Kunth | map | |
| Cenchrus tribuloides L. | map | images (1) (2) (3) |
| Centaurea biebersteinii DC. | map | |
| Centaurea cyanus L. | map | images (1) (2) |
| Centaurea solstitialis L. | map | |
| Centella erecta (L.f.) Fern. | map | |
| Centrosema virginianum (L.) Benth. | map | images (1) (2) (3) |
| Cephalanthus occidentalis L. | map | images (1) (2) |
| Cerastium brachypetalum Desportes | map | |
| Cerastium brachypodum (Engelm. ex Gray) B.L. Robins. | map | |
| Cerastium fontanum Baumg. ssp. vulgare (Hartman) Greuter & Burdet | map | |
| Cerastium glomeratum Thuill. | map | images (1) |
| Cerastium nutans Raf. | map | images (1) (2) |
| Cerastium pumilum W. Curtis | map | |
| Cerastium semidecandrum L. | map | |
| Ceratiola ericoides Michx. | map | images (1) (2) (3) (4) |
| Ceratophyllum demersum L. | map | |
| Ceratophyllum echinatum Gray | map | |
| Cercis canadensi L. | map | images (1) (2) (3) |
| Chaerophyllum procumbens (L.) Crantz var. procumbens | map | |
| Chaerophyllum procumbens (L.) Crantz var. shortii Torr. & Gray | map | |
| Chaerophyllum tainturieri Hook. var. dasycarpum Hook ex S. Wats. | map | |
| Chaerophyllum tainturieri Hook. var. tainturieri | map | images (1) (2) |
| Chamaecrista fasciculata (Michx.) Greene | map | images (1) (2) (3) (4) |
| Chamaecrista nictitans (L.) Moench var. aspera (Muhl. ex Ell.) Irwin & Barneby | map | images (1) (2) |
| Chamaecrista nictitans (L.) Moench var. nictitans | map | |
| Chamaecyparis thyoides (L.) B.S.P. | map | images (1) |
| Chamaedaphne calyculata (L.) Moench var. angustifolia (Ait.) Rehd. | map | |
| Chamaelirium luteum (L.) Gray | map | |
| Chamaesyce bombensis (Jacq.) Dugand | map | |
| Chamaesyce cordifolia (Ell.) Small | map | images (1) (2) |
| Chamaesyce hirta (L.) Millsp. | map | |
| Chamaesyce maculata (L.) Small | map | |
| Chamaesyce nutans (Lag.) Small | map | images (1) (2) |
| Chamaesyce polygonifolia (L.) Small | map | |
| Chamaesyce prostrata (Ait.) Small | map | |
| Chaptalia tomentosa Vent. | map | images (1) (2) (3) |
| Chasmanthium latifolium (Michx.) Yates | map | images (1) |
| Chasmanthium laxum (L.) Yates | map | |
| Chasmanthium nitidum (Baldw.) Yates | map | |
| Chasmanthium sessiliflorum (Poir.) Yates | map | images (1) (2) (3) |
| Cheilanthes lanosa (Michx.) D.C. Eat. | map | images (1) |
| Cheilanthes tomentosa Link | map | images (1) (2) (3) |
| Chelone glabra L. | map | images (1) (2) |
| Chelone lyonii Pursh | map | |
| Chelone obliqua L. | map | |
| Chenopodium album L. | map | images (1) |
| Chenopodium ambrosioides L. | map | images (1) (2) |
| Chenopodium multifidum L. | map | |
| Chenopodium murale L. | map | |
| Chenopodium pratericola Rydb. | map | |
| Chenopodium pumilio R. Br. | map | |
| Chenopodium standleyanum Aellen | map | |
| Chimaphila maculata (L.) Pursh | map | images (1) |
| Chionanthus virginicus L. | map | images (1) (2) |
| Chloris virgata Sw. | map | |
| Chrysogonum virginianum L. var. australe (Alexander ex Small) Ahles | map | |
| Chrysogonum virginianum L. var. virginianum | map | images (1) |
| Chrysoma pauciflosculosa (Michx.) Greene | map | images (1) (2) |
| Chrysopsis gossypina (Michx.) Ell. | map | images (1) (2) (3) (4) |
| Chrysopsis mariana (L.) Ell. | map | images (1) (2) (3) (4) |
| Chrysopsis pilosa Nutt. | map | |
| Chrysopsis scabrella Torr. & Gray | map | |
| Chrysosplenium americanum Schwein ex Hook. | map | |
| Cichorium intybus L. | map | |
| Cicuta maculata L. | map | |
| Cicuta mexicana Coult. & Rose | map | |
| Cimicifuga americana Michx. | map | |
| Cimicifuga racemosa (L.) Nutt. | map | |
| Cinna arundinacea L. | map | |
| Cinnamomum camphora (L.) J. Presl. | map | images (1) |
| Circaea lutetiana L. ssp. canadensis (L.) Aschers & Magnus | map | |
| Cirsium altissimum (L.) Hill | map | |
| Cirsium carolinianum (Walt.) Fern. & Schub. | map | |
| Cirsium discolor (Muhl. ex Willd.) Sprengel | map | |
| Cirsium horridulum Michx. var. horridulum | map | images (1) (2) (3) |
| Cirsium horridulum Michx. var. vittatum (Small) R.W. Long | map | |
| Cirsium lecontei Torr. & Gray | map | |
| Cirsium muticum Michx. | map | |
| Cirsium nuttallii DC. | map | images (1) (2) (3) |
| Cirsium pumilum (Nutt.) Spreng | map | |
| Cirsium repandum Michx. | map | |
| Cirsium virginianum (L.) Michx. | map | |
| Cirsium vulgare (Savi) Ten. | map | images (1) |
| Citrullus lanatus (Thunb.) Matsumura & Nakai | map | images (1) (2) |
| Cladium jamaicense Crantz | map | |
| Cladium mariscoides (Muhl.) Torr. | map | |
| Cladrastis kentukea (Dum.-Cours.) Rudd | map | |
| Claytonia virginica L. | map | images (1) (2) (3) |
| Cleistes divaricata (L.) Ames | map | |
| Clematis catesbyana Pursh | map | |
| Clematis crispa L. | map | images (1) (2) (3) (4) |
| Clematis glaucophylla Small | map | |
| Clematis ochroleuca Ait. | map | |
| Clematis reticulata Walt. | map | |
| Clematis terniflora DC. | map | |
| Clematis viorna L. | map | |
| Clematis virginiana L. | map | images (1) (2) |
| Cleome gynandra L. | map | |
| Cleome hassleriana Chod. | map | |
| Clerodendrum indicum (L.) Kuntze | map | images (1) (2) (3) |
| Clethra acuminata Michx. | map | |
| Clethra alnifolia L. | map | images (1) (2) |
| Cliftonia monophylla (Lam.) Britt. ex Sarg. | map | |
| Clintonia umbellulata (Michx.) Morong | map | |
| Clitoria mariana L. | map | |
| Cnicus benedictus L. | map | |
| Cnidoscolus stimulosus (Michx.) Engelm. & Gray | map | images (1) (2) |
| Cocculus carolinus (L.) DC. | map | images (1) |
| Coelorachis cylindrica (Michx.) Nash. | map | |
| Coelorachis rugosa (Nutt.) Nash | map | |
| Collinsonia canadensis L. | map | images (1) (2) (3) |
| Collinsonia serotina Walt. | map | |
| Collinsonia tuberosa Michx. | map | |
| Collinsonia verticillata Baldw. | map | |
| Comandra umbellata (L.) Nutt. | map | |
| Commelina communis L. | map | images (1) (2) |
| Commelina diffusa Burm. f. | map | images (1) |
| Commelina erecta L. | map | images (1) (2) (3) |
| Commelina virginica L. | map | images (1) (2) |
| Comptonia peregrina (L.) Coult. | map | |
| Conium maculatum L. | map | images (1) (2) (3) (4) (5) |
| Conopholis americana (L.) Wallr. f. | map | images (1) |
| Consolida ambigua (L.) P.W. Ball & Heywood | map | |
| Convallaria majuscula Greene | map | |
| Convolvulus arvensis L. | map | |
| Conyza bonariensis (L.) Cronq. | map | images (1) (2) (3) |
| Conyza canadensis (L.) Cronq. var. canadensis | map | images (1) |
| Conyza canadensis (L.) Cronq. var. pusilla (Nutt.) Cronq. | map | |
| Corallorhiza odontorhiza (Willd.) Nutt. | map | |
| Corallorhiza wisteriana Conrad | map | images (1) (2) |
| Coreopsis auriculata L. | map | |
| Coreopsis basalis (A. Dietr.) Blake | map | |
| Coreopsis delphiniifolia Lam. | map | images (1) (2) |
| Coreopsis gladiata Walt. | map | |
| Coreopsis grandiflora Hogg ex Sweet | map | |
| Coreopsis helianthoides Beadle | map | |
| Coreopsis integrifolia Poir. | map | |
| Coreopsis lanceolata L. | map | images (1) (2) |
| Coreopsis latifolia Michx. | map | |
| Coreopsis linifolia Nutt. | map | |
| Coreopsis major Walt. | map | images (1) (2) |
| Coreopsis pubescens Ell. | map | |
| Coreopsis rosea Nutt. | map | |
| Coreopsis tinctoria Nutt. | map | |
| Coreopsis tripteris L. | map | |
| Coreopsis verticillata L. | map | |
| Coriandrum sativum L. | map | |
| Cornus alternifolia L. f. | map | |
| Cornus amomum P. Mill. | map | |
| Cornus asperifolia Michx. | map | |
| Cornus florida L. | map | images (1) (2) (3) (4) |
| Cornus foemina P. Mill. | map | images (1) (2) |
| Cornus racemosa Lam. | map | |
| Coronilla varia L. | map | images (1) (2) |
| Coronopus didymus (L.) Sm. | map | images (1) (2) |
| Cortaderia selloana (J.A. & J.H. Schultes) Aschers. & Graebn. | map | |
| Corydalis flavula (Raf.) DC. | map | images (1) (2) |
| Corydalis micrantha (Engelm. ex Gray) Gray ssp. australis (Chapman) G.B. Ownbey | map | |
| Corydalis micrantha (Engelm. ex Gray) Gray ssp. micrantha | map | |
| Corydalis sempervirens (L.) Pers. | map | |
| Corylus americana Walt. | map | images (1) |
| Corylus cornuta Marsh. | map | |
| Cosmos bipinnatus Cav. | map | |
| Crataegus aestivalis (Walt.) Torr. & Gray | map | |
| Crataegus crus-galli L. | map | images (1) |
| Crataegus flabellata (Spach) Kirchn. | map | images (1) (2) |
| Crataegus flava Ait. | map | |
| Crataegus marshallii Egglest. | map | |
| Crataegus phaenopyrum (L. f.) Medik. | map | |
| Crataegus punctata Jacq. | map | |
| Crataegus spathulata Michx. | map | |
| Crataegus uniflora Muenchh. | map | images (1) |
| Crataegus viridis L. | map | |
| Crepis pulchra L. | map | images (1) (2) (3) |
| Crinum americanum L. | map | |
| Crinum bulbispermum (Burm. f.) Milne-Redhead & Schweikerdt | map | |
| Crocosmia x crocosmiiflora (V. Lemoine ex E. Morr.) N.E. Br. | map | |
| Croptilon divaricatum (Nutt.) Raf. | map | images (1) (2) |
| Crotalaria brevidens Benth. var. intermedia (Kotschy) Polhill | map | images (1) |
| Crotalaria incana L. | map | |
| Crotalaria lanceolata E. Mey. | map | |
| Crotalaria ochroleuca G. Don. | map | |
| Crotalaria pallida Ait. | map | images (1) (2) (3) (4) |
| Crotalaria purshii DC. | map | images (1) |
| Crotalaria rotundifolia Walt. ex J.F. Gmel. var. vulgaris Windler | map | images (1) (2) (3) |
| Crotalaria sagittalis L. | map | |
| Crotalaria spectabilis Roth | map | images (1) (2) (3) |
| Croton capitatus Michx. | map | |
| Croton elliottii Chapman | map | |
| Croton glandulosus L. var. septentrionalis Muell.-Arg. | map | images (1) (2) |
| Croton michauxii Webster | map | images (1) (2) |
| Croton punctatus Jacq. | map | images (1) (2) |
| Croton willdenowii Webster | map | images (1) (2) (3) |
| Cruciata pedemontana (Bellardi) Ehrend | map | |
| Cryptotaenia canadensis (L.) DC. | map | images (1) (2) (3) |
| Ctenium aromaticum (Walt.) Wood | map | images (1) (2) |
| Cucumis melo L. | map | |
| Cucumis sativus L. | map | |
| Cucurbita pepo L. | map | |
| Cunila origanoides (L.) Britt. | map | |
| Cuphea carthagenensis (Jacq.) J.F. Macbr. | map | |
| Cuphea viscosissima Jacq. | map | images (1) |
| Cuscuta cephalanthi Engelm. | map | |
| Cuscuta compacta Juss. ex Choisy | map | |
| Cuscuta coryli Engelm. | map | |
| Cuscuta gronovii Willd. ex J.A. Schultes | map | |
| Cuscuta indecora Choisy | map | |
| Cuscuta japonica Choisy | map | |
| Cuscuta pentagona Engelm. | map | |
| Cuscuta rostrata Shuttlew. ex Engelm. & Gray | map | |
| Cuthbertia graminea Small | map | images (1) (2) (3) |
| Cuthbertia rosea (Vent.) Small | map | images (1) (2) (3) (4) |
| Cycloloma atriplicifolium (Spreng.) Coult. | map | |
| Cyclospermum leptophyllum (Pers.) Sprauge ex Britt. & Wilson | map | |
| Cynanchum angustifolium Pers. | map | images (1) (2) (3) |
| Cynanchum laeve (Michx.) Pers. | map | |
| Cynanchum scoparium Nutt. | map | |
| Cynodon dactylon (L.) Pers. | map | images (1) (2) |
| Cynoglossum virginianum L. | map | |
| Cynosurus echinatus L. | map | |
| Cyperus articulatus L. | map | |
| Cyperus bipartitus Torr. | map | |
| Cyperus compressus L. | map | images (1) (2) |
| Cyperus croceus Vahl | map | |
| Cyperus cuspidatus Kunth | map | |
| Cyperus dentatus Torr. | map | |
| Cyperus difformis L. | map | images (1) |
| Cyperus distinctus Steud. | map | images (1) |
| Cyperus echinatus (L.) Wood | map | |
| Cyperus erythrorhizos Muhl. | map | images (1) (2) |
| Cyperus esculentus L. | map | |
| Cyperus flavescens L. | map | images (1) (2) |
| Cyperus flavicomus Michx. | map | |
| Cyperus granitophilus McVaugh | map | |
| Cyperus grayi Torr. | map | |
| Cyperus haspan L. | map | images (1) (2) (3) (4) |
| Cyperus hystricinus Fern. | map | |
| Cyperus iria L. | map | images (1) (2) (3) |
| Cyperus lancastriensis Porter ex Gray | map | |
| Cyperus lecontei Torrey ex Steudel | map | |
| Cyperus lupulinus (Spreng.) Marcks | map | |
| Cyperus odoratus L. | map | |
| Cyperus pilosus Vahl | map | |
| Cyperus plukenetii Fern. | map | images (1) (2) |
| Cyperus polystachyos Rottb. var. filicinus (Vahl) C.B. Clarke | map | |
| Cyperus polystachyos Rottb. var. polystachyos | map | |
| Cyperus pseudovegetus Steud. | map | |
| Cyperus refractus Engelm. ex Boeckl. | map | images (1) (2) |
| Cyperus retrofractus (L.) Torr. | map | |
| Cyperus retrorsus Chapman var. cylindricus (Ell.) Fern. & Grisc. | map | |
| Cyperus retrorsus Chapman var. retrorsus | map | |
| Cyperus retrorsus Chapman var. robustus (Boeckl.) Kukenth | map | |
| Cyperus rotundus L. | map | images (1) |
| Cyperus squarrosus L. | map | |
| Cyperus strigosus L. | map | |
| Cyperus surinamensis Rottb. | map | |
| Cyperus tetragonus Ell. | map | |
| Cyperus virens Michx. | map | images (1) (2) |
| Cypripedium acaule Ait. | map | |
| Cypripedium parviflorum Salisb. var. pubescens (Willd.) Night | map | |
| Cyrilla racemiflora L. | map | images (1) (2) (3) (4) |
| Cyrtomium falcatum (L. f.) K. Presl | map | images (1) (2) (3) |
| Cyrtomium fortunei J. Sm. | map | |
| Cystopteris bulbifera (L.) Bernh. | map | |
| Cystopteris protrusa (Weatherby) Blasdell | map | |
| Cystopteris tennesseensis Shaver | map | |
| Cytisus scoparius (L.) Link | map | |