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Forest Pest

Be on the lookout for a few very destructive pests. Pests are grouped by the pest, or location and type of the symptoms.

Forest Insect Pest

Asian Longhorned Beetle (Anoplophora glabripennis)

Trees Affected
Norway, sugar, silver, and red maple, horsechestnut, aspen (poplar), willow, elm, mulberry, and black locust and other hardwoods.

Symptoms
Very round rust colored holes (entry and exit wounds) about 3/8 to 1/2" in diameter along the branches or trunk of the tree.

Importance
Extremely destructive exotic pest that once established can kill hardwoods very rapidly.

Prevention
Early detection and prompt removal of dead or dying trees.

Learn More
Current Status, Research, and Management of the Asian Longhorned Beetle

Asian longhorned beetle

Asian longhorned beetle

Asian longhorned beetle

Round rust colored holes left by the Asian longhorned beetle.


 

Balsam Woolly Adelgid



Trees Affected
All true furs, Abies spp., including balsam and fraser fir.

Symptoms
Infested crowns with abnormal drooping of current shoots and gouting of outer twigs. Crown becomes increasingly thin and dieback may occur. Stem attacks with conspicuous presence of white woolly masses often giving the lower bole a whitewashed appearance. Sapwood of infested wood swells causing gouting of twigs and increased heartwood formation.

Importance
A serious pest of forest, seed production, landscape, and Christmas trees. Stem infestations are usually more serious, causing greater levels of damage and mortality. Persistent crown infestation can kill a tree over a number of years.

Prevention
Early detection and prompt removal and destruction of dead or dying trees. Prescribed fire is often used to sanitize the site.

balsam whooly

Balsam fir bark infected with Balsam Woolly Adelgid.

balsam whooly

Gall-like formation on the twigs, due to Balsam Woolly Adelgid feeding.

balsam whooly

Balsam fir needles infected with Balsam Woolly Adelgid.

Hemlock Woolly Adelgid


Trees Affected
Eastern hemlock (Tsuga canadensis) & Carolina hemlock (T. caroliniana).

Symptoms
White cottony masses at the base of needles.

Importance
Destructive disease that can quickly kill hemlock.

Prevention
Early detection and treatments to avert establishment of populations.

Learn More
USDA Forest Service Hemlock Woolly Adelgid Site

Hemlock Woolly Adelgid

Hemlock Woolly Adelgid

Dieback on Eastern Hemlock due to Hemlock Woolly Adelgid.

Foliage Dieback

A number of forest pests directly or indirectly affect the foliage on trees. Some pests eat or chew on the leaves or needles while other pests may injure parts of the tree which led to foliage dieback.

Oak Wilt

Trees Affected
White, and Red Oak

Symptoms
Bronzing or browning of green leaves from the tips/margins toward the leaf base.

Importance
Destructivedisease that can kill oaks very rapidly.

Prevention
Early detection and prompt removal of dead or dying trees. Avoid trimming, or cutting live oak trees during spring (May - June).

 

oak wilt

Oak wilt symptoms on red oak leaves.

oak wilt defoliation

Oak wilt defoliation.