Credit Valley Conservation is educating local residents about invasive and native plants.
The CVC's original plan for Tuesday morning (July 16) was to guide volunteers as they pulled invasive species from Hungry Hollow, near Metcalfe Court and Delrex Boulevard.
But as the sky darkened and the deluge of the day began, the CVC pivoted to a quick lesson about the importance of planting native species over invasive ones.
“They’re going to reduce the biodiversity of the area. They're not great for wildlife. Buckthorn specifically is actually a diuretic. It goes right through a bird’s system. It is a way for the plant to spread itself through its seeds. It’s not healthy for local birds,” CVC Community Outreach Coordinator Kristen Valencia said.
“They out-compete native species from growing. They do so by changing the soil chemistry. For example, garlic mustard is known to do that. It changes the pH level and makes it too basic,” Program Assistant with the CVC’s community outreach department Brittany Stoneman explained.
Human intervention is one of the major reasons why invasive species arrive in any ecosystem, let alone southern Ontario. Buckthorn is native to Europe and Asia, but farmers brought it to North America to use as windrows. Its seeds have spread great distances, causing issues across many regions in the province.
Garlic mustard was brought here for its culinary and medicinal uses. Its seeds adhere to clothes and animal fur, causing it to spread far and wide.
Several ornamental plants from abroad are also contributing to the issue.
“A lot of people think if there is greenery and green space, this is great,” Valencia noted in speaking about common misconceptions around planting. “It doesn’t necessarily help out the ecosystem. We need more native plants.”
Garlic mustard and the common buckthorn are two types invasive species pulled the most by the CVC in their area of concern. Others include, but are not limited to:
- The Manitoba maple
- The European spindle tree
- Winged euonymus, sometimes called the burning bush
- Forsythias
- False spirea
- Norway maple
- Black alder
- Giant mana grass
- Common reed
- Lily of the valley
- Winter aconite
- English ivy
- Japanese pachysandra, sometimes called spurge.
The CVC website contains a wealth of information about invasive and native species and what to do with them. Phone apps like iNaturalist made it easy to identify plants and even say if the plant is native or not. Keep an eye on the CVC's events page for other gatherings similar to the invasive species pull.
