List of invasive plant species in the Indiana Dunes
The Indiana Dunes is an area of land beside Lake Michigan, in the State of Indiana, United States. It includes the Indiana Dunes National Lakeshore and the Indiana Dunes State Park. This article is about non-native plant species, specifically the invasive species which have colonized that area. Invasive plants are those plants that aggressively spread throughout an area and out-compete other plant species, normally those that are native to the area.
"These species can have a negative affect on the local economy, the environment and public health. Most non-native plants were introduced as farm products or for home gardens. Others have arrived on the feet, hull, or tires of people and animals passing through. While many non-native plants are relatively harmless, the term invasive has been reserved for the most aggressive of species." 
Invasive plant species can have, and have had, several negative impacts:
- Some of these plants can overgrow trails and roads,
- Some can entangle bike chains, e.g. knapweed
- They can displace the variety of flowering plants, substituting a monoculture
- They can introduce toxins into the environment, e.g. the sap of the leafy spurge
- In some cases they have spines or thorns, e.g. thistles
- Some invasive aquatic plants can smoother ponds, killing fish
- Some invasive plants can create navigation barriers for small boats
Plants of special interest
- Purple Loosestrife – establishes a monoculture, reducing the variety of wildlife.
- Bush Honeysuckles – prevents regeneration of woody plants and herbs, reducing bird habitat.
- Glossy Buckthorn – prevents regeneration of woody plants, slowly destroying forests.
- Garlic Mustard – alters the chemistry of the soil to kill other seeds, creating a monoculture.
- Asian Bittersweet – this vine can kill or damage trees and shrubs.
- Crown Vetch – alters the soil chemistry and pushes out the variety of other plants.
- Japanese Knotweed – tolerates floods and drought, creates a monoculture.
- Spotted Knapweed – releases toxins into the soil to poison its competition.
- Common Reed – this introduced non-native species aggressively pushes the native species and other aquatic plants out of the ecosystem.
- Canada Thistle – successfully competes for space in prairies, savannas and dunes.
Species established within the Dunes
Current Threats 
Emerging threats to natural resources or extent unknown
- Indiana Dunes National Lakeshore
- Indiana Dunes State Park
- Introduced species
- Invasive species
- List of invasive species
- List of invasive species in North America
- The Singing Sands; National Park Service, Indiana Dunes National Lakeshore, Summer 2009, Vol. 30 No.1