Garlic Mustard was introduced in the 1800s for medicinal purposes and for cooking. Now, it is widely dispersed throughout the country and can be found in all parts of the state. The wildflowers in the mountains are most threatened by Garlic Mustard as it is shade tolerant and can compete with the flowers for the same habitat in woodlands. It also produces allelopathic compounds which inhibit the germination of other species' seeds. Humans and wildlife are most responsible for long-distance seed dispersal.
During its first year, the plant forms rosettes of kidney-shaped leaves. In its second year, it grows heart-shaped leaves (2 - 3") with deeply serrated edges. It will also produce a tall stalk (1 - 4') with small white flowers in spring. Flowers have 4 petals and grow in clusters. Seed pods are long, slender, and green and have shiny black seeds. The plant is distinguished by a slender white taproot and a garlic odor when stems and leaves are crushed.
Fact Sheet: Garlic Mustard
Photo credit: Chris Evans, River to River CWMA, Bugwood.org