Biocontrol of Yellow Toadflax using Rhinusa pilosa, in Prince Albert National Park

Yellow toadflax is a widely distributed perennial invasive plant that reproduces by seed and extensive creeping rhizome. The plant is extremely hardy and  has the ability to densely infest large areas and crowd out native vegetation, making it a threat to ecological integrity in Prince Albert National Park. Herbicide spraying of yellow toadflax has occurred in several locations in Prince Albert National Park with limited success. Using a biological control agent offers an additional option for control of this species in a manner that is not nearly so labour intensive.  Prince Albert National Park will be working with Agriculture and Agri-food Canada to carry out trials of Rhinusa pilosa in up to three affected locations - Prospect Point, Rabbit Cabin area and 12 Mile Meadow. Weevils will be obtained from Agriculture and Agri-foods Canada at no charge and will be released at the sites in late summer.

Latest update

March 10, 2021 - The assessment decision statement has been issued to the proponent.



Prince Albert National Park
Box 100
Waskesiu Lake, Saskatchewan S0J 2Y0
Telephone: 306-663-4522 or 1-888-773-8883

  • Location

    • Prince Albert National Park (Saskatchewan)
  • Nature of Activity

    • Remediation and conservation
  • Assessment Status

  • Start Date

  • Proponent

    Parks Canada
  • Authorities

    • Parks Canada Agency
  • Assessment Type

    Project on federal lands
  • Reference Number


This map is for illustrative purposes. The markers represent the approximate locations based on available data. More than one marker may be identified for a given assessment.


Nearby assessments

...within 200 kilometres
Date modified: