Japanese Butterbur (Petasites japonica) CKISS

Japanese Butterbur

Petasites japonica


  • Perennial, herbaceous plant with an almost tropical appearance that can grow up to 6 feet tall
  • Similar in appearance to rhubarb
  • Simple, kidney-shaped leaves can grow up to 3 ft across, with dense hairs on the underside
  • Single leaves grown on ridged, hollow stems
  • Flowers are white to pink and grow on a spike that emerges before leaves in the late winter/early spring
  • Native to Asia, likely brought to North America as an ornamental
  • Its scientific name comes from the Greek word petasos, meaning a wide-brimmed hat
  • Found in shaded areas with moist soil, including river banks, shorelines, wetlands, and ditches

Consequences of invasion

  • Spreads easily by rhizomes or rhizome fragments and sometimes through seed
  • Large leaves can shade and outcompete native vegetation, leaving bare ground beneath which can lead to increased erosion.

Status in the CKISS region

Currently classified as Eradicate in the region.

  • It is present in the region with limited distribution, so eradication is feasible
  • CKISS is taking steps to monitor and manage Japanese butterbur
  • To learn more about how CKISS classifies and manages invasive species, see our Invasive Species Priority Lists page.

Integrated pest management options

Mechanical Treatment:

  • Can be time-consuming and labor-intensive with large infestations
  • Pull or dig up plants when the soil is moist to control small infestations, ensuring to dig up all rhizome material

Additional resources

Japanese Butterbur (Petasites japonica)