A diversity of native plant species is vital to healthy forests and grasslands. Certain plant species can threaten the ecological integrity, or health, of Elk Island National Park’s ecosystems. Often these problematic plants are non-native and / or invasive, and have the ability to spread quickly and outcompete native plants.

Some plants cannot be eaten by animals like bison, either because they’re not palatable or because they are toxic. An overabundance of these plants reduces the amount of food available for the parks animals by choking out native plant species the animals prefer. A plant that is harmful to animals or the environment is called a noxious weed. For example, if a pregnant bison eats Common Tansy, she could get sick and lose her calf. To prevent the rapid spread of noxious weeds staff apply herbicides and manually remove plants.

The following invasive plants have been targeted at Elk Island. If you see these plants while visiting the park, if possible, take a photo and the GPS coordinates or location description and email them to elk.island@pc.gc.ca (use “Invasive Plants” in the subject line).

  • Leafy Spurge (Euphorbia esula)
  • Common burdock (Arctium spp.)
  • White cockle (Silene latifolia)
  • Field scabious (Knautia arvensis)
  • Common tansy (Tanacetum vulgare)