Invaders of Wisconsin

Japanese Stilt Grass (Microstegium vimineum)
Purple Loosestrife (Lythrum salicaria)
Reed Canary Grass (Phalaris arundinacea L.)	UW Herbarium Photographer: Stephen L. Solheim
Black Locust Robinia pseudoacacia L.	UW Herbarium Photographer Michael Clayton
Future Wetland Invaders: Plants To Watch For by Kelly Kearns, WDNR Plant Conservation Program Manager, for Wisconsin Wetlands Association

Foreigners in Wisconsin's Woods
Three major culprits

Forests are important to Wisconsin in many ways. They provide habitat for wildlife, recreation for tourists, and protection for our watersheds. They are also being invaded on a major scale by nonnative plants.

These invaders shade out native vegetation and reduce the health of the forest. They can have long-term significance for forest survival.

The important thing is to detect their presence early and initiate immediate eradication. If you detect one of these invaders in your woods, waiting for another year is not an option. Eradication should start now.

Fortunately, all three of these species can be controlled by standard, approved, methods. Click on the link for each to see species-specific control measures.

The three most important invaders of Wisconsin's forests are:

Garlic mustard (Alliaria petiolata)	garlic mustard
Common buckthorn (Rhamnus cathartica)	buckthorn
Honeysuckle (species of Lonicera)	honeysuckle

Phragmites webpage by the Wisconsin Wetlands Association

The following links take you to the Wisconsin DNR Invasive Species website:

Multiflora Rose (Rosa multiflora)
Spotted Knapweed (Centaurea maculosa)
Leafy Spurge (Euphorbia esula)
Eurasian Water Milfoil (Myriophyllum spicatum)
Wild Parsnip (Pastinaca sativa)

New Weeds to Watch For

Weed Rank Forms from the Hiawatha National Forest

Additional Widespread and Known Invasive

Glossy buckthorn

Dame's Rocket

Canada thistle

Phragmites, Common Reed

Autumn Olive

Curly leaf pondweed

Narrow-leaf and hybrid cattail

Oriental bittersweet

Bird’s foot trefoil

Crown vetch

White and yellow sweet clovers

For additional information about these and other plants, see our Links page.