Nature Conservancy of Canada issues warning about Japanese knotweed

The Nature Conservancy of Canada is warning people to be on the lookout for Japanese knotweed.

The aggressive weed grows in bamboo-like clumps and has heart-shaped leaves, according to spokesperson Andrew Holland.

Holland says the invasive species threatens to overrun local plants, and its extensive root system can damage infrastructure, such as bridges and buildings.

"It is able to grow through concrete and asphalt up to eight centimetres thick and building foundations," said Holland.

The plant can grow as much as eight centimetres a day, said Holland, and typically reaches heights of between one and three metres tall.

Japanese knotweed can be found throughout Canada and the northeastern United States, he said.

It grows in a wide range of habitats such as wetlands, roadsides, ditches, utility right of ways and fence lines.

"It is a vigorous plant that can take over areas to the detriment of our native species," said Holland. "It outcompetes them, takes their nutrients away from those trees, and negatively impacts wetland and water's edge areas."

You can remove the weed on your own, but Holland said it can take up to five year to kill the plant completely.

He encouraged people who are not comfortable removing it to contact their municipality or a professional.