Garlic Mustard

Garlic mustard is a cool season biennial herb in the mustard family with stalked, triangular to heart-shaped, coarsely toothed leaves that give off an odor of garlic when crushed.

Photo: Dan Tenaglia, www.missouriplants.com, www.invasives.org

Photo: Chris Evans, Univ. of Georgia, www.invasives.org Photo: Chris Evans, The Univ. of Georgia, www.invasives.org

First-year plants appear as a rosette of green leaves close to the ground. Rosettes remain green through the winter and develop into mature flowering plants the following spring.

Photo: Jody Schimp, Illinois Dept. of Natural Resources, www.invasive.org

Flowering plants of garlic mustard reach from 2 to 3-1/2 feet in height and produce buttonlike clusters of small white flowers, each with four petals in the shape of a cross.

Photo: Chris Evans, The Univ. of Georgia, www.invasives.org

Photo: Britt Slattery, U.S. Fish and Wildlife Service, www.invasive.org

ECOLOGICAL THREAT

Garlic mustard poses a severe threat to native plants and animals in forest communities. Many native widlflowers that complete their life cycles in the springtime (e.g., spring beauty, wild ginger, bloodroot, Dutchman's breeches, hepatica, toothworts, and trilliums) occur in the same habitat as garlic mustard. Once introduced to an area, garlic mustard outcompetes native plants by aggressively monopolizing light, moisture, nutrients, soil and space. Wildlife species that depend on these early plants for their foliage, pollen, nectar, fruits, seeds and roots, are deprived of these essential food sources when garlic mustard replaces them. Humans are also deprived of the vibrant display of beautiful spring wildflowers.  Recent research indicates that garlic mustard kills the mycorrhizae which is a type of fungus that assists the growth of trees and other native plants in a healthy forest.

Photo: Victoria Nuzzo, Natural Area Consultants, www.invasive.org.