Caragana shrub invades Calgary’s natural areas as city starts removal program

City of Calgary work to control Caragana growth
WATCH ABOVE: Calgary prides itself over the number of trees and natural areas in the city, but some of that land is threatened by invasive plants which are choking out other growth. One species is called Caragana and there is a major effort to control it. Tony Tighe reports.

A plant imported from Asia decades ago is taking over parkland in Calgary and choking out other plants.

The City of Calgary parks department has started a program to cut back and remove Caragana from five parks this spring and summer. Baker, Edworthy, St. Andrew’s, South Glenmore and River parks are the areas in question.

“It tends to crowd out other species,” said Chris Manderson, the urban conservation lead with the city. “It eliminates a lot of the other plants that grow around it, shades them out actually, and in some cases prevents them from germinating.”

He says to have healthy, sustainable natural areas, they have to control this plant and encourage other native growth.

They’ll be cutting and mulching the plants, then treating the stumps and the soil with herbicide to prevent further growth.

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For more information on the city’s removal program, click here

Caragana is not a weed and is legal to sell at garden centres.

Arborists say homeowners have to be careful, because the plant  grows very fast–up to a metre a year–and requires regular maintenance.

“If you let it grow, it’s going to be as tall as a tree, and when it reaches a height of like 20 feet, if you have wind or snowfall, they will just fall apart,” said Paul Saindon, the owner of Your Tree Doctor.

He is currently pruning a large number of Caragana at a Calgary condo complex after the shrubs were considered a safety hazard.