Crofton Weed 
Culebra Thistle 
Cup Plant 
Cupid's dart 
Cushion Fanflower 
Cutleaf coneflower 
Cyananthus inflatus 
Cymbolaena 
Dahlia x hortensis 
Dampiera lanceolata 
Dampiera sylvestris 
Deer Cabbage 
Dense Blazing Star 
Desert Marigold 
Desert yellow fleabane 
Desertbroom 
Devil's Beggarticks 
Devil's Grandmother 
Devil's Tobacco 
Diamond-leaved bellflower 
Dicoma incana 
Diffuse Knapweed 
Diplostephium ericoides 
Diplostephium hartwegii