News Release

FREDERICTON (CNB) – Localized defoliation caused by the forest tent caterpillar is expected to reoccur this year in the Bathurst, Fredericton and French Village areas.

Defoliation of aspen trees by the tent caterpillar occurred in those communities and other areas last year. The Forest Pest Management Section of the Department of Natural Resources forecasts defoliation will occur again this year. The caterpillar was recently observed in Fredericton.

Tent caterpillars are a widespread pest of aspen and other hardwood trees and periodically defoliate millions of hectares in other jurisdictions. The last two outbreaks in New Brunswick (1979-84; 1991-96) covered 1.4 million hectares (3.4 million acres) and 400,000 hectares (988,000 acres), respectively.

Tent caterpillars are often referred to as armyworms because the larvae become very mobile and move about the ground in massive numbers looking for more trees to attack. Large numbers often crawl up the sides of buildings and other property and become a nuisance.

Caterpillars emerge from eggs in mid- to late-May and generally feed for about a month before pupating and changing into brownish moths about two weeks later. The feeding larvae have a distinctive row of key-hole shaped white dots down their backs bordered by two blue lines .

Populations are controlled naturally by predators, parasites and disease, although it may take several years before the tent caterpillar populations collapse. There are no plans to conduct a spray program.

Property owners can take a number of steps to reduce damage:

●    keep defoliated or damaged trees well watered to prevent any additional stress – defoliated trees will typically produce another crop of leaves in the same year;
●    prevent caterpillars from migrating into trees by applying a pest barrier such as tanglefoot over a band on the tree trunk in the spring after leaves flush; and
●    after moths have disappeared, check the crowns of small hardwoods for the black egg bands laid on branch twigs and remove and destroy them before they can hatch next season.

LINKS:

●    Department of Natural Resources: www.gnb.ca/naturalresources
●    Canadian Forest Service: www.cfs.nrcan.gc.ca
●    Pest Management Regulatory Agency