Creeping Zinnia
Creepingroot Violet
Creosote Bush
Crescent Milkvetch
Crested Anoda
Crested Coralroot
Crestrib Morning-glory
Cretanweed
Crimson Bluestem
Crimson Fountaingrass
Crimson Sage
Crinkleawn Grass
Crinklemat
Crispleaf Buckwheat
Crossflower
Croton
Crowfoot Grass
Crowfoot Rockdaisy
Crown Mayweed
Crown Of Thorns
Crownbeard
Crowndaisy
Crowngrass
Crownleaf Evening Primrose
Crownvetch
Crucifixion Thorn
Cryptantha
Cuban Jute
Cudweed
Cultivated Radish
Cuman Ragweed
Cupgrass
Cupped Passionflower
Curl-leaf Mountain Mahogany
Curly Dock
Curly Pondweed
Curly-mesquite
Curlycup Gumweed
Curlyhead Goldenweed
Curlyleaf Muhly
Curlytop Gumweed
Curlytop Knotweed
Currant
Cursed Buttercup