Why are these volunteers so happy? Because they just uprooted and bagged a bunch of invasive garlic mustard (Alliaria petiolata). During two A Rocha-coordinated workdays in May and June at the Oak Ridges Moraine Land Trust’s StarCliff Nature Reserve in King Township north of Toronto, volunteers removed the plant from an approximately 200 square metre area of land.

Garlic mustard (aka poor man’s garlic) is one of the most invasive terrestrial species in Southern Ontario. Spreading aggressively in settled areas, the plant was introduced from Europe for its value as a nutritious–but pungent–food. No longer a significant source of food for humans (this could be changed!), garlic mustard has no native predators nor any other natural controls to keep it in check. Furthermore, because it is biennial (it remains living through the winter and produces seeds in its second year, following which it dies) and it alters soil chemistry, it displaces native species to the point where it dominates a forest’s understory and prevents its regeneration.

Although the area that this garlic mustard was removed from was not large, controlling its spread at this early stage is significant.  Vigilance is needed as there is still first-year growth in the area where the second-year growth was removed and because the plant’s seeds remain viable in the soil for approximately five years.  Therefore, volunteers will continue to control the growth of garlic mustard at StarCliff. Following its hopeful eradication, regular monitoring will continue.

Regular workdays at the property are coordinated by Paul Abell, A Rocha’s Stewardship Coordinator.  The efforts of volunteers help make it possible for the StarCliff Nature Reserve to thrive as a habitat for a wide variety of native species. To get a smile like one of these volunteers, send an email to ontario@arocha.ca and join us on a workday.