Invasive Plants

Invasive plants are species that are not native to a particular ecosystem and cause harm to that environment, economy, or even human health. These plants tend to spread rapidly via seed or rhizomes and out compete native plants for resources, which can lead to a reduction in diversity. This can have a cascading effect on the ecosystem, affecting animals and other organisms that rely on native plants for food and habitat.

Invasive plants do untold damage to Ontario’s natural areas, displacing native plants and overtaking sensitive habitats. These aggressive invaders wreak havoc and the cost of their removal is steep for conservation authorities and municipalities. Many nurseries still sell invasive plants, exacerbating the spread. Most home gardeners are not aware that plants growing in their garden can potentially damage and degrade natural ecosystems. The photo above shows invasive periwinkle in the TJ Dolan Natural Area, Stratford. This plant escaped from nearby home gardens backing on the natural area and it has overrun the native trilliums, ferns, trout lily and wild leeks.

The list below from Credit Valley Conservation Authority is the recognized comprehensive list of invasive plants in Ontario. If you have plants in your garden that are listed under Category 1 or Category 2, you should prioritize their removal as soon as possible.

The Ontario Invasive Plant Council has an excellent booklet, Grow Me Instead, which can help gardeners find alternatives to invasive plants. Below is a link to the site to download the booklet. 

For more information on invasive plant regulation and control, visit the CCIPR website. CCIPR, the Canadian Coalition for Invasive Plant Regulation, is an organization attempting to improve policies and regulations to stop the sale of invasive plants in Canada. They are lobbying for the labelling of plants that are potentially invasive, as well as a code of conduct for the horticulture industry.