Subject
- Champion trees 16
- Chemical plants 5
- Children8
- Cicadas2
- City Year (Service corps)85
- Clearing of land 5
- Cliffs 4
- Climbing hempweed1
- Common moonwort1
- Congaree National Park (S.C.)2,158
- Congaree River (S.C.)27
- Congaree River (S.C.) 90
- Congaree Swamp (S.C.) 1
- Construction85
- Construction 1
- Coreidae1
- Corydalis1
- Cottonwood1
- Crabapples1
- Crocodiles14