Canada thistle – English ivy
- Weeds: Canada thistle – Cirsium arvense
- Weeds: Catchweed bedstraw (Cleavers) – Galium aparine
- Weeds: Catsear, common (False dandelion) – Hypochaeris radicata
- Weeds: Chickweed, common and mouseear – Stellaria media, Cerastium fontanum ssp. vulgare
- Weeds: Clover – Trifolium spp.
- Weeds: Comfrey – Symphytum officinale
- Weeds: Crabgrass – Digitaria spp.
- Weeds: Creeping Jenny: Lysimachia nummularia
- Weeds: Dandelion – Taraxacum officinale
- Weeds: Dock (Curly, Broadleaf) – Rumex spp.
- Weeds: Dodder – Cuscuta spp.
- Weeds: Downy brome (Cheatgrass, Downy chess) – Bromus tectorum
- Weeds: Dwarf mistletoes – Arceuthobium spp.w
- Weeds: English daisy (Lawn daisy) – Bellis perennis
- Weeds: English ivy – Hedera helix