Illinois Bundleflower
Illinois Pinweed
Illinois Pondweed
Illscented Wakerobin
Indian Blanket
Indian Breadroot
Indian Cucumber
Indian Goosegrass
Indian Heliotrope
Indian Lovegrass
Indian Mallow
Indian Paintbrush
Indian Plantain
Indian Strawberry
Indian Woodoats
Indian-tobacco
Indiangrass
Indianhemp
Indianpipe
Indigo
Inflated Narrow-leaf Sedge
Inland Bluegrass
Inland Muhly
Inland Rush
Inland Sedge
Interior Phacelia
Intermediate Mermaidweed
Intermediate Woodfern
Interrupted Fern
Iodanthus
Ipomopsis
Iris
Irisleaf Yelloweyed Grass
Ironweed
Italian Gladiolus
Italian Leather Flower
Italian Ryegrass
Ivy
Ivyleaf Morning-glory
Ivyleaf Speedwell