How to Identify Insect Damage to Maple Trees

The sugar maple is the most prolific maple species in North America.

Maple trees are one of the predominate species that provide spectacular fall foliage. Heavy damage by insects can retard growth and defoliate the trees. Tree lovers that maintain maple trees in their landscape should regularly inspect their maple trees for signs of insect infestation. Early detection allows you to research and implement the safest method of freeing the tree from the pests that inhabit your maple trees, which can speed removal and curtail damage.

Things You'll Need

• Insect guide book

Instructions

1. 

   Aphid infestation

   Examine your maple trees. A close examination of your maple tree will generally evidence of some type of insect feeding or show symptoms of decline including leaf loss, peeling bark, deformed growth or evidence of damage such as curling leaves, wilting or yellowing is visible. Insects that attack maple trees and may cause damage are cyclical. According to the Vermont Department of Forests, Parks & Recreation, manifestations will vary depending on weather conditions that may encourage or deter the infestation.

2. Look for webs or cocoons evident on the tree limbs or underside of leaves. Cracks or holes in maple leaves are often evidence of caterpillar forage. Aphids flourish in hot, humid conditions and will stunt new growth. Maple trees with established leaves will show signs of twisting, drooping leaves or other evidence of damage. Check for spots or bumps on the underside of leaves, a sign of spider mites.

3. 

   Red maple leaves

   Identify the type of insect that is infecting your maple trees. The sugar maple borer (Glycobius speciosus)--the most destructive to the trees--is yellow and black with a W-shaped marking on the wing span. Two small black dots are at the base of each wing. Maple trees infested with maple sugar borers will show evidence of a dark, wet stain on the exterior bark. If the infestation persists, the tree will evidence a thinning crown, lose branches and may eventually die.

4. Familiarize yourself with the insects that attack maple trees. Maple trees are subject to numerous insects that may affect the health of the tree. The principle offenders include the bruce spanworm, forest tent caterpillar, sugar maple borer, maple leaf cutter, pear thrips and saddled prominent. The Asian long-horned beetle is another threat to maple trees.

5. Research the insects you find infesting your maple trees. Obtain an insect guide book, helpful in identifying a particular bug with which you may not be familiar. If in doubt, contact your local county extension office. Take a sample of the leaf or limb damage and an insect to their offices for identification and treatment recommendations.

Tips & Warnings

• Introduce ladybugs into your landscape to control aphid infestations. You can purchase ladybugs online or from home and garden supply centers.

References

• University of Rhode Island Horticulture Program: Maple Tree Decline
• Vermont Department of Forests, Parks & Recreation: Maple Health
• Tree Help: Maple Trees
• Hubbard Brook Research Foundation: Susceptibility of Declining Sugar Maple to Foliar Damage