Garlic mustard is an invasive non-native biennial herb that spreads by seed. Although edible for people, it is not eaten by local wildlife or insects. This was introduced by Europeans as a food source.

It is difficult to control once it has reached a site; it can cross-pollinate or self-pollinate. In other words, one plant can end up producing a whole colony of plants. It has a high seed production rate which has been estimated at 62,000 per square yard! This enables it to out compete native vegetation.

Its very adaptable and can grow in sun or shade. The fact that it is self fertile means that one plant can occupy a site and produce a seed bank. Plant stands can produce more than 62,000 seeds per square meter to quickly out-compete local flora, changing the structure of plant communities on the forest floor. Garlic mustard is also allelopathic, which means it makes the soil around it “poisonous” for other plants, ensuring its survival.