Illinois Bundleflower
Illinois Flatsedge
Illinois Pinweed
Inchplant
Incised Agrimony
Indian Blanket
Indian Breadroot
Indian Cucumber
Indian Goosegrass
Indian Heliotrope
Indian Jointvetch
Indian Lovegrass
Indian Mallow
Indian Paintbrush
Indian Plantain
Indian Shot
Indian Strawberry
Indian Toothcup
Indian Woodoats
Indian-tobacco
Indiangrass
Indianhemp
Indianpipe
Indigo
Inflated Narrow-leaf Sedge
Inflatedscale Flatsedge
Inkberry
Inland Muhly
Inland Rush
Interior Ironweed
Intermediate Mermaidweed
Intermediate Paspalum
Intermediate Pepperweed
Ipomopsis
Iris
Irish Potato
Irisleaf Yelloweyed Grass
Ironweed
Italian Ryegrass
Itchgrass
Ivy
Ivyleaf Groundcherry
Ivyleaf Morning-glory
Ivyleaf Speedwell