'Like seeing a friend in its demise': Yarmouth beech trees threatened by invasive species

Forty years ago, David Sollows planted a seedling that became a treasured beech tree on his Yarmouth, N.S., property.

He loves how the tree looks, the privacy it offers and how birds flock to it, but the tree's existence is threatened because of an invasive species called the beech leaf-mining weevil, a type of beetle.

From afar, the burgundy-coloured tree looks fine. Close up, the telltale sign of infestation shows in leaves with gaping holes.

"It's like seeing a friend in its demise," said Sollows.

The arrival of the mining weevil in the Yarmouth area was first noticed a few years back, but the problem has grown significantly worse since then.

At Thursday's town council meeting, a motion is being introduced asking for a staff report to look into what can be done about the problem.

"It's one of those things that if you don't get it out there in the public, people don't become aware of it and they don't realize how severe the problem is," said Coun. Gil Dares.

Beech trees are plentiful in Yarmouth, said Sollows. He said during Victorian times, it was a species that was deliberately planted in the community.

"They'll live to be 150 to 200 years old, easily," said Sollows.

The infestations cause the trees to lose large amounts of foliage, resulting in them getting progressively weaker. Within a few years, the trees can die.

Mining weevils have been reported in other parts of Nova Scotia, such as Halifax, Wolfville and Cape Breton.

Andrew Hebda, retired curator of zoology at the Nova Scotia Museum, said it's unclear when the mining weevils first arrived in the province from Europe, but pegs it around 15 years ago.

"The basic issue is in order to be able to control them, you can't spray and kill them by contact, which is what most chemical control is," he said.

Hebda said there's work involving the Canadian Forestry Service being done to inject an insecticide into beech trees, but the approach is time consuming and expensive.

Hebda said while the mining weevils are from Europe, they aren't as big a problem there because of how other species co-evolved, noting there are some parasitic organisms there that help keep them in check.

He said introducing those species here could bring unintended consequences.

"So what is going to be the impact of introducing a biological control?" said Hebda.