Insects That Kill Oak Trees

Oak trees appear mighty and impenetrable at first glance. Unfortunately, many insects prey on these trees and can destroy them. The insect colonies attack and kill oak trees by their sheer volume. Ridding oak trees of insects quickly is the best way to protect them.

Locusts are extremely harmful to oak trees for years at a time. Just one female punctures the tree's limbs for 24 to 28 eggs. According to the Forest Health Protection Organization, nymphs fall to the ground and eat the tree's roots for up to 17 years.

Oak lace bugs are prevalent on white oak trees on the East Coast. These insects are only a one-fourth inch long, but their colonies can be very large. Nymphs feed on the leaves of white oak trees, interfering with photosynthesis. The average time from egg laying to the mature adult stage is approximately one month. As a consequence, numerous oak lace bugs can kill a tree.

Similar to the oak lace bugs, aphids damage the oak tree's leaves. Aphids feed on the bottom side of oak leaves, which become curled. The aphids can cause stunted tree growth in spring and summer. Aphids attack white and red oak trees more often than other varieties.

Oak trees are susceptible to photosynthesis interference, fungus and mold resulting from attacks on the leaves. Plants and trees cannot survive without photosynthesis. These problems, over time. can kill oak trees.

Borers are a group of insects that tunnel within shrubs and trees. Oak tree damage can be continuous during the life cycle of these insects, which ranges from one to four years. Beech borer, spotworm borer, flathead appletree borer, oak branch borer and oak-stem borer are the most common borers that kill oak trees.

Borers live just below the oak tree's bark on both the trunk and branches. They overwhelm the tree's limbs, branches and trunk by eating the tree's life support system. The insects lay larvae throughout the tree. Saplings and newly transplanted trees are most vulnerable to attacks--and death--by borers.