Japanese stiltgrass

Japanese stiltgrass (Microstegium vimineum) is an invasive plant found in many habitats, including forests, wetlands and disturbed areas.

Because of how fast it spreads, it can disturb ecosystems by out-competing native plants and affecting bird nests and other wildlife.

Japanese stiltgrass spreads when its seeds attach to clothing or animal fur. Seeds can also be found on muddy car tires and shoes. Bird seed, soil, nursery stock and hay can also be contaminated with Japanese stiltgrass.

Report a Japanese stiltgrass sighting

Where it's found

Japanese stiltgrass has been confirmed in a small population under official control in southern Ontario, including:

  • Waterloo Park
  • Short Hills Provincial Park

What you can do

  • When leaving a forested area in Southern Ontario, including national and provincial parks, help stop the spread of Japanese stiltgrass seeds by brushing off your:
    • clothes
    • shoes
    • bikes, and
    • pets.
  • Avoid planting invasive plants in your garden.
  • Use clean, high-quality seeds that are certified for your garden to avoid accidentally planting an invasive specie.
  • Ensure your machinery, vehicles and tools are free of soil and plant parts before moving from one area to another.
  • Report sightings of Japanese stiltgrass to the Canadian Food Inspection Agency.

How to spot it

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Image 4
  • Image 1 : Leaves
  • Image 2 : Foliage in the spring and summer
  • Image 3 : Foliage in the fall
  • Image 4 : As a grain, spikelet and seed (from left to right)

Japanese stiltgrass is an annual grass that sprawls across the floors of disturbed areas, forests and wetlands, as it prefers lower light. Stems can grow up to 1 m tall and have many branches. Leaf blades are thin, pale green and tapered at both ends. In late summer, slender flower spikes are found at the end of the stems. Plants develop a slightly purplish colour in autumn.

What we are doing

Japanese stiltgrass is regulated as a pest in Canada under the Plant Protection Act. Importation and domestic movement of regulated plants and their propagative parts is prohibited.

More information

 
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