Invasive Species | Terrestrial Plants

Garlic Mustard

Photo: Mary C Legg, Mary C Legg, Bugwood.org

Originally brought to North America from Europe in the 1800’s as a edible garden herb, Garlic Mustard is an aggressive plant that forms dense stands in early spring, monopolizing resources and shading out native species. It is avoided by deer, who then over-browse native species, and is allelopathic - meaning it inhibits the growth of other plants around it by releasing biochemicals into the surrounding soil.

Garlic Mustard

(Alliaria petiolata)

French common name: Dompte-venin de Russie/dompte-venin noir et pâle


Characteristics

Chris Evans, University of Illinois, Bugwood.org

Life cycle: biennial herb with two different growth stages; reproduces by seed, commonly produces up to 600 seeds per plant.

1st Year Growth: dark green, kidney-shaped leaves that grow low to the ground in rosettes; leaves have scalloped margins and smell like garlic when crushed.

2nd Year Growth: tall, flowering stalks (up to 1m); triangular leaves with toothed margins that alternate along the hairy stem.

Flowers & Seed Pods: clusters of small white flowers with of 4 petals that emerge in early May; develop into long seed pods (2.5-6cm) that contain 10-20 small seeds each.

Habitat: Commonly found in forested and other partial or fully shaded areas but adaptable to a wide variety of conditions; thrives in disturbed areas.

Key ID Features

Rob Routledge, Sault College, Bugwood.org

Distinct garlic smell when leaves are crushed, particularly in first year.

Steven Katovich, Bugwood.org

Extensive ‘carpeting’ of ground at both growth stages in heavily infested areas.


Common Look-a-Likes

Karan A. Rawlins, University of Georgia, Bugwood.org

Wild Violets (Viola ssp):

  • Leaves are heart-shaped with shallow toothed margins, >1.5m tall

  • More prominent palmate leaf veins

Chris Evans, University of Illinois, Bugwood.org

Wild Ginger (Asarum canadense):

  • Each plant has 2 large velvety heart-shaped leaves and a single flower at the base


How It’s Spread

This plant was introduced as a garden species and has been moved into new areas through dumping of garden clippings or movement of garden materials. Learn more about invasive plant species and how you can help to prevent the spread of invasive species when gardening on our Plant Wise program page.

Resources