Work to protect forest goes on, despite no spray program

Gary Kean
Published on August 5, 2014

There may not be any aerial control program for pests this year, but that doesn’t mean there is no work going on to ensure the health of the province’s forests.

According to the Department of Natural Resources, this summer is just the third time in the last 37 years that there have been no aerial operations to control outbreaks of voracious pests such as the hemlock looper, spruce budworm or balsam fir sawfly.

“The only time we ever do a control program is when there’s a need to do so,” said Dan Lavigne, supervisor of forest insect and disease control with the Department of Natural Resources in Corner Brook.

Of all the major forest pests posing a threat to the forest resource, Lavigne is most concerned these days about the growing outbreak of spruce budworm in Quebec.

In 2013, the spruce budworm chewed up some 3.2 million hectares in Quebec. This year, the critters are expected to impact another four million hectares. Because the spruce budworm moth is a capable flyer, Lavigne’s concern is that some of Quebec’s budworms may catch some westerly winds and find their way to Newfoundland. It is likely that female moths who find their way across the Gulf of St. Lawrence may still have half their complement of eggs left to lay.

The surveys Lavigne and his staff conduct involve the use of pheromone traps. Using the chemical secreted by the female insect, male specimens are lured to the trap where they die and are collected for the survey.

The same model of trap is used for the different species, but the same trap cannot be used for a different species if it already has the scent of another insect pheromone on it.

Insects are not the only threat to trees in the forest.

In fact, the only control work to be conducted in the province in 2014 will be the destruction of red pine infected with a serious invasive disease of hard pines called scleroderris canker.

The Avalon Peninsula is currently a quarantine zone for red pine, meaning no living pine material is allowed to be brought west of the isthmus that separates the Avalon from the rest of Newfoundland. Outside that quarantine zone, seven locations have been identified as being infected with scleroderris canker. Most of these zones are found along Route 360, the Bay D’Espoir highway. There is only one zone in western Newfoundland, namely at a red pine plantation in Cold Brook, just outside of Stephenville.

Lavigne will be meeting with his staff to discuss their plans to destroy the living pine at these seven sites to prevent the spread of the disease to other red pine plantations and indigenous red pine areas. A plan has been approved by the Department of Environment and Conservation, with a condition that the work is done outside the nesting season of red crossbill birds and other species that live in the pine habitat.

The department will cut down the infected trees and burn them, but will try to save merchantable wood possible, said Lavigne.

It is still not clear how scleroderris canker managed to spread outside the quarantine zone as it is usually spread only by rain splash and spores carried on mist.

One theory, said Lavigne, is that it was transported by people who took infected pine from the Avalon for use as firewood outside the zone.

Bug talk:

Based on surveys done last year, populations of the troublesome bugs that like to eat certain species of trees were forecast to be low across the island portion of the province and in Labrador.

With the hemlock looper, the lone exceptions on the island are two small, localized areas in Middle Cove and Tors Cove Pond on the Avalon Peninsula where populations are expected to be active in non-commercial forest areas. Levels of hemlock looper in Labrador are expected to remain low, as they have been since the collapse of the last outbreak in 2009.

Populations of spruce budworm have been on the rise in Eastern Canada, particularly along the northern and Gaspe shores of the St. Lawrence River. In Newfoundland, there have been some increases detected in populations of spruce budworm moths in western Newfoundland, but the levels are still not high enough to require implementing a control program.

The spruce budworm is expected to be active in the Goose Bay area of Labrador, but most of the areas it will affect will be outside the Forest Management District 19a, which includes the majority of Labrador’s closed canopy forest.

The balsam fir sawfly feasted on western Newfoundland’s forests for years, but has mostly subsided in recent seasons. The fly is expected to be active in the St. Alban’s area for a third straight summer, but its outbreaks are expected to be short-lived because of a naturally occurring virus and no control measures have been deemed necessary.