Arboricultural staff in Fredericton are monitoring for an invasive insect that kills ash trees.

They have installed lime green prism traps in 20 locations throughout the city to see if they will catch any emerald ash borers.

Don Murray, the manager of parks and trees, and the city’s forester, says while they’ve been watching for the pest for 10 to 12 years, they haven’t found any indication of it being in the city yet.

“We do that by surveillance in the field and we also check ash trees that we suspect have this pest in it,” said Murray. “We haven’t found any yet.”

The pest can be in the area damaging trees for five to seven years before being noticed without the surveillance, he said.

“This pest gets under the bark of the tree, it will lay eggs under the bark of the tree and these little grubs will hatch and start boring,” Murray described. “And as they bore they will start to cut the water supply off and the nutrient supply off to the tree and the tree goes into decline.”

All the native ash trees in the province — black ash, white ash, and green and red ash — are susceptible to invasion by the pest, he said.

When asked how close the pest was to New Brunswick, Murray said, “Like I tell everybody, it’s less than a day’s drive away. It’s in the Montreal area and it’s also in the southern part of New Hampshire which is too close for comfort for us.”

In an inventory of trees done for the City of Fredericton, 11 per cent were ash trees. “That accounts for 2,400 ash trees on our streets,” said Murray.

Traps important

Murray said the pests are hard to see after they become adults and can fly up into the tree canopy. “They are green, the leaves are green so it’s tough to see them. That’s why the traps are so important.”

The traps are checked mid-season and at the end of the season.

Murray said if an adult beetle is trapped, they would notify the Canadian Food Inspection Agency to begin to work on a plan to eradicate the pest.

Part of that early eradication process is to remove any ash tree in a certain proximity from the location where the pest was found.

Murray said tens of millions of ash trees were destroyed across Canada because of the pest.

“Now, you do a removal program on the less-valuable ash trees and there’s actually a product called TreeAzin that can be injected in your tree that will kill off the grubs or the larvae in the tree or the beetle that’s feeding on it.”

Murray said cutting down an ash tree would be the last resort if the emerald ash borer does invade.

“We are going to develop a plan to help deal with this,” he said. “If we can find this in year one, year two, it gives us a much better chance of controlling it. If we don’t find it until year five, year seven, we’re probably losing the battle already.”

Murray said if a homeowner thinks they have the pest in their ash trees to call him as soon as possible.