A European herb gone rogue, Garlic Mustard is threat to our future forests.
Species Name: Garlic Mustard (Alliaria petiolata)
Description: A green herbaceous plant with heart-shaped leaves and a pungent, garlic-like odor when crushed. In the plant's first year, the plant grows low to the ground and produces a rosette of 4 to 8 leaves. In the second year, the plant grows erect, up to several feet tall, produces triangular leaves and a flower stalk with four-petaled white flowers and later, seed pods. Garlic Mustard will grow in a variety of places, in forests and along roadsides.
Similar species: Cut-leaved toothwort (Cardamine concatenata), Sweet cicely (Osmorhiza claytonia and O. longistylis), and Early saxifrage (Saxifraga virginica) all look similar and grow in the same habitats as Garlic Mustard. Only Garlic Mustard has the combination of broad, heart-shaped leaves, four-petaled flowers, and a garlic odor.
Origin: Europe, likely planted for food and medicine in the United States in the mid-nineteenth century.
How it spreads: Garlic Mustard produces an abundance of small seeds that can easily become established in areas with disturbed soil. Seeds also can remain viable up to five years in the soil.
Extent in Michigan: Found throughout the state and in surrounding states.
Why is Garlic Mustard a problem: Garlic Mustard can outcompete native plants, especially trees in the understory of our forests. Once established, it is difficult to get rid of Garlic Mustard as it can resprout from the roots, is not as palatable as native plants to herbivores, and produces many, long-lasting seeds.
Management actions/options: Garlic Mustard can be managed through hand pulling and herbicide treatments, though large areas will require subsequent years of treatment. The best method of control is prevention and early response to established plants. Be mindful of activities that will cause soil disturbance and consider the consequences of where to dispose of yard waste. Clean soil off of shoes and tires before moving from forest to forest. If you spot it, report it.
REPORT IT: Use the Midwest Invasive Species Information Network Reporting tool online
or download their reporting app
Links and References:
US Forest Service: https://www.na.fs.fed.us/spfo/invasiveplants/factsheets/pdf/garlic-mustard.pdf