Invasive Species

Invasive plant species are non-native weeds that are known to spread aggressively and have the potential to create monocultures when they are not removed.

These invasive species crowd out many native wildflowers and gain an ecological edge that impacts natural landscapes. Wildlife can be harmed by invasive plants when greenspaces lack species diversity and the native plants in which they depend upon for survival.

There are many volunteer opportunities to get involved in Northbrook with ecological restoration to remove invasive plants in our natural areas, like the Somme Preserves. But when invasive plants are allowed to thrive on private properties, the valiant efforts of natural restoration champions become less effective. 

Community members can help defeat invasive plants by recognizing and removing them. The following plant species are specified in Northbrook’s municipal code as invasive:

  • Purple Loosestrife
  • Multiflora Rose
  • Jimsonweed
  • Common Burdock
  • Teasels (Common & Cutleaf)
  • Ragweed (Common & Giant)
  • Thistles (Canada, Bull, Musk and Sowthistle)

 Identification Guide

Use the chart below to identify these species, or download the pdf version here

Invasive Plant Management and Control

Controlling these aggressive invasive plant species can take multiple methods of action and several attempts. Herbicides should only be used when absolutely necessary and by carefully following instructions on the label. Use the links below to find best practices for each of these species.


Buckthorn Considerations

Northbrook’s municipal code defines a specific set of plant species as invasive, and buckthorn is not on this list. Buckthorn is considered an invasive species by many because it is non-native and can spread aggressively. Others find it to be a good shrub for screening and privacy. It takes a lot of effort to remove the plant completely, and possibly necessitates the use of herbicide spraying. The Village has the following pamphlet for more info on buckthorn.