Cabbage
Cabbage Palmetto
Cactus Apple
Caddo False Foxglove
Caesarweed
Caladium
Calamus
Caley Pea
Calibrachoa
Calico Aster
California Bulrush
California Nettle
California Plantain
California Poppy
Callery Pear
Calycocarpum
Calyptocarpus
Camas
Campernelle Jonquil
Camphor Daisy
Camphor Pluchea
Camphortree
Camphorweed
Campion
Campsis
Canada Bluegrass
Canada Cocklebur
Canada Germander
Canada Goldenrod
Canada Lettuce
Canada Spikesedge
Canada Toadflax
Canadian Blacksnakeroot
Canadian Clearweed
Canadian Honewort
Canadian Horseweed
Canadian Lousewort
Canadian Milkvetch
Canadian Rush
Canadian Wildginger
Canadian Woodnettle
Canary Island Tamarisk
Canarygrass
Cancerwort