Tricky problem: Invasive Himalayan blackberry plant discovered in Yarmouth

Nova Scotia faces a new invasive species that could outcompete low vegetation and native fruit.

The Nova Scotia Invasive Species Council says the Himalayan blackberry was discovered in Yarmouth, making it a first for the province.

Despite its name, the thicket-forming shrub is not native to the Himalayan mountains, but to the Armenian region.

Council supervisor Kirsten Noel said the plant was discovered last week at a few different sites in Yarmouth, including along the Yarmouth County Waterfront and Rail Trail.

« We suspect it was intentionally planted in a garden by someone who probably didn’t realize how invasive or aggressive it was, » Noel said.

She said « aggression » is what sets her apart from native blackberries.

It can grow up to five meters tall and uses canes – long, thin branches – to move around. The canes can reach over 10 meters in length and root wherever they touch the ground, helping them to create new plants.

The berries themselves are a little larger than those grown on native species, lack the trademark hairs, and taste a little more tart.

Himalayan blackberry bushes are also dense and covered in thorns, creating tall walls that can block access to waterways and trails.

“They don’t grow in harmony with our native species,” Noel said. « Most of the time, invasive species compete with our native species for important resources like food, nutrients or space. Ultimately, this could reduce biodiversity. »

Part of the appeal of the berry plantation is its fruit production, said David Sollows, president of the UNESCO Southwest Nova Biosphere Reserve Association. He said this is especially true as the plant will flower and bear fruit continuously until frost sets in.

Sollows said it was crucial to control the plant in the early stages of its spread.

« Once it has established itself in things like fields and areas intended for agriculture, it can create very dense barriers of huge, thorny branches that are pretty much impenetrable, » he said. declared.

It is likely that part of the spread of the plant is due to birds eating the berries and dropping the seeds. Sollows added that climate and coastal exposure can also play a role in plant performance at Yarmouth.

Although this is the first appearance of the plant in Nova Scotia, it has already been seen in other Canadian jurisdictions. British Columbia has long cared for this plant, which has been found in the Lower Mainland and Vancouver Island.

Noel said the council will likely be able to control the growth of the plant because it was detected early. She said the group plans to contact other invasive species councils that have dealt with the berries to get an idea of ​​the best course of action.

Eventually, a management plan will be developed outlining how the council will deal with existing mills.

“This could include awareness raising and education, as well as [manually] cut the bushes, dig them up,” Noel said. “It’s definitely something that’s on our priority list now that we know it’s there.”

Sollows echoed the sentiment and said education is an important part of mastering the berry plant.

« Convincing the public that you really don’t want it…can be a challenge, » he said. « It’s a plant that will end up costing municipalities and farmers money to eradicate it. »