Nova Scotia

Japanese knotweed blooming in Dartmouth, Halifax

The invasive Japanese knotweed continues to wreak havoc across the Halifax region.

Left to grow wild, the invasive weed threatens native species

There is a curtain of Japanese knotweed hiding a bus stop on Mount Edward Road in Dartmouth. It's the latest example of the very aggressive invasive species making itself home here in Nova Scotia.

Perry Falconer, owner of PetRide Halifax, sees it everywhere while he's on the road.

"Two days into summer and they're already taller than me, so that's how fast they grow," said Falconer.

This Japanese knotweed in Dartmouth is overgrowing the sidewalk. (Anjuli Patil/CBC News)

Japanese knotweed has a bamboo-like stalk and heart shaped leaves. When it grows wild, it threatens to overrun local plants. It can grow through concrete and it only takes a small part of the plant for it to spread.

"This little area next to me here, there's a birch tree in the middle of it and its leaves are all dry and dead but all the knotweed around it is all nice and green, so it's probably taking all the nutrients away from the tree," said Falconer.

"It's a vigorous plant that can take over areas and it's to the detriment of our native species," said Doug van Hemessen, Nova Scotia stewardship coordinator for the Nature Conservancy of Canada.

van Hemessen said he has seen the weed around Lunenburg County. He said if you see it on your property, remove it as soon as possible.

"It's been shown that there's a loss of animal diversity... frogs especially, where you get a stand of knotweed that — in a wet area that previously was a great spot for different kinds of frogs — once the knotweed is there, the frogs are gone and the native plants are gone and the insects associated with those also disappear."

The city of Halifax is also aware the Japanese knotweed is out. It wants residents to call 311 to report any spotted on municipal property.