Distribution Garlic mustard is native to Europe. In North America, it occurs primarily in the northeast with isolated populations in British Columbia and Oregon. The southwestern Ontario counties of Middlesex and Elgin, as well as the larger urban centres, such as Toronto and Ottawa are the main areas of abundance for the species. Cavers et al . The first Canadian record of garlic mustard is from Toronto in 1879.
Solid circles represent individual or local occurrences.
During the first year, the plant produces a slender taproot and a basal rosette of leaves that persist over the winter. Cavers et al . It is clear that garlic mustard is displacing native species in some natural areas, however, detailed ecological studies need to be conducted to assess the degree of impact. Present Status and Potential Threat Garlic mustard presently occurs in a limited portion of Canada-primarily southern Ontario. Cavers et al .