Invasive Species

Explore why invasive plants are a concern in the St. Louis region and learn what you can do to help address them. 

Invasive Plants 101

What is an Exotic Species?

Exotic species are those that do not naturally occur in our region, but have been introduced by humans, either intentionally or accidentally, allowing the species to cross a natural barrier to dispersal.

It is true that the native range of plants can naturally expand in response to climate change and other factors over long periods of time. However, the introduction of exotic plants by humans allows the species to cross some barrier to dispersal, such as an ocean, vast desert, or mountain range, which prohibits natural range expansion.

While the introduction of exotic species such as insects or fungal pathogens is typically accidental, the vast majority of exotic plant species are introduced intentionally for purposes such as ornamental landscaping, livestock forage, and agriculture.

Why Should You Care?

What Can You Do To Help?

Learn to identify invasive plant species in our region (see Species List below) and how to distinguish them from any native species that are similar in appearance.

Avoid using invasive plants in your garden. Until you are able to get rid of invasive plants in your yard, be responsible and remember to remove and destroy seeds of invasive plants to prevent their dispersal into natural areas. Don’t share invasives with other gardeners.  Ask your local nursery not to sell invasive plants and to provide native alternatives.

Don’t plant invasive plants for wildlife. Native species provide much better food and cover for native wildlife.

Volunteer to help remove invasive species in local parks and natural areas.

Pass it on! Tell your friends and family about the threat from invasive species.

Invasive Species in the St. Louis Region