<Callirhoe alcaeoides. 53
Callirhoe involucrata. 58
Calylophus berlandieri. 21
Calylophus lavandulifolius. 17
Calylophus serrulatus. 20.
Camphor weed. 147
Castilleja purpurea var. citrina. 247
Catchweed bedstraw. 34
Chamaesaracha coniodes. 89
Chrysopsis villosa var. villosa. 161.
Ciliate goldenweed. 151
Cirsium undulatum. 196
Cirsium vulgare. 197
Clammyweed. 8
Columnar coneflower. 124
Commelina erecta. 2
Common devil's claw. 234
Common evening primrose. 22
Common goldenrod. 142
Common groundcherry. 94
Common mallow. 69
Common prickly pear. 119
Common sunflower. 156
Common yarrow. 138
Convolvulus arvensis. 96
Convolvulus equitans. 97
Croton texensis. 261
Cryptantha jamesii. 84
Cryptantha minima. 85
Cryptantha. 85
Cucurbita foetidissima. 92
Cupseed stickseed. 83
Cursed crowfoot. 45
Cutleaf ironplant. 159

Dakota verbena. 70
Dalea aurea. 224
Dalea enneandra. 213
Dalea purpurea. 281
Dandelion. 175
Dayflower. 2
Delphinium virescens. 225
Desmanthus illinoensis. 260
Downy goldenrod. 146
Dyssodia papposa. 139.