Management of Non-Native Hybrid Cattails

Voyageurs National Park (VNP) supports approximately 20,000 to 27,000 acres of wetlands. Many wetland areas throughout Voyageurs have been invaded by non-native hybrid cattails which are displacing native vegetation by forming dense stands or large subsurface mats. These invasions pose a threat to park resources due to a reduction in aquatic habitat biodiversity, and a reduction in overall diversity within all impacted ecosystems. These invasions alter the dynamics of aquatic ecosystems and limit use of waterways for recreation and park operations.

Hybrid cattail invasions are having the largest impact on the shoreline ecosystems, creating large dense monocultures. These monocultures can grow to very large sizes creating mats that cover entire bays. This is causing a variety of problems related to the natural resources and the visitor's use of the park. These issues are:

- The hybrid cattails are invasive and are spreading to new locations.

- Floating mats break off in windy conditions creating navigation hazards and facilitate the spread of cattails.

- The invasive nature of hybrid cattails leads to habitat degradation.
• Muskrat and other wildlife habitat is diminished.
• Fish spawning areas are reduced.
• Vegetation biodiversity is reduced.

- The visitor experience is hampered. Canoeing, fishing, and wildlife viewing opportunities are reduced.

- The cattails can choke out shorelines and boat docking areas creating the need for periodic maintenance to remove the vegetation.

To address these issues, Voyageurs National Park has prepared an Environmental Assessment (EA) for the removal of invasive hybrid cattail and the subsequent restoration of native marsh plant communities. The EA explores alternatives for treatment or removal of cattails and restoration of native plants.

Contact Information

Bryce Olson, Biologist
phone: 218-283-6694