7 Common Pests And Insects That Can Damage Your Tree

Tree insects and diseases can harm your tree and some can even cause tree death. If you suspect that your tree is infested, you should hire arborist services or read this guide. Quick detection is required because insects and diseases can spread to the surrounding trees and landscaping of your yard as well, so learn which insects are dangerous and the signs your tree is infested.

Common Tree Pests

Gypsy Moth

Also called spongy moths, gypsy moths are common tree defoliator pests. Their impact is huge because they can defoliate millions of acres of trees in a single year. The damaging phase begins in spring when gypsy moths find a tree and leave enormous numbers of eggs on it.

When these eggs are hatched into larvae, they eat the leaves of the tree in a huge amounts. These larvae can eat one square foot of leaves a day. As they continue to increase their population, they can completely defoliate a large number of trees.

Trees that are prone to gypsy moth infestation are oak, linden, beech, willow, birch, crabapple, and others.

To spot eggs of gypsy moth, look at the tree trunk to find yellowish small egg masses that can have about 500 eggs.

Western Tent Caterpillar

They are a type of tent-making caterpillars that attack aspen, cottonwood, willow, and fruit trees. Western tent caterpillars can defoliate a tree completely if the outbreak is severe. You will notice large silk-like tents on branches that clearly show that the tree is under attack.

The damage caused by the western tent caterpillars is typically from May to June. For early detection, look for brown foliage at the top and outer branches of the tree. If your tree is defoliated multiple times, it can lead to growth loss, branch dieback, and tree death as well.

Eastern Tent Caterpillar

These are also similar to western Tent caterpillars, but they infest trees in the Eastern US. They also form silk tents on branches of trees. Easter tent caterpillars commonly attack cherry, crabapple, apple, hawthorn, pear, maple, peach, and plum trees. You should look for silk tents and stripped leaves as signs of eastern tent caterpillar infestation.

Asian Longhorn Beetle

They can fly from one tree to another but they lay eggs on the same tree from where they were hatched. Therefore, they are easier to control than other tree bugs. They can damage plane-tree, elm, willow, and platanus trees.

To detect if your tree is infested by Asian longhorn beetles, look for dust-like or sweet sap excrement on the branches of the tree and the trunk. You should also keep an eye on the leaves as they can cause yellowing and unseasonale drooping of the leaves. On the bark of the tree, there may be chewed parts.

The size of Asian longhorn beetles is around one inch so they can be seen around the tree and the surrounding landscape of a tree is infested with them. They have long horns that are bigger than their bodies.

They are dangerous tree borers and can severely harm your tree resulting in tree death. To prevent them, inspect your tree bark and branches regularly for sawdust, holes, or stunted growth. Moreover, firewood can contain and move them so check the firewood before moving.

If your tree is already infested by Asian longhorn beetles, your tree may be dying. Have the tree inspected and if the damage has been done, you’re better off getting the tree removed by a tree cutting service Bethesda to prevent them from attacking other trees and plants in your yard.

Scale Insects

They like to attack a tree in the springtime and favor lilac, dogwood, willow, maple, and ash trees. Scale insects are difficult to detect because they commonly reside in the inner parts of a tree’s bark. They can stunt the growth of your tree and if not removed, they can be fatal for your tree.

For detecting scale insects, check the leaves and stems of your tree. Infested trees will have scales on the central leaf veins and on the back of the leaves and stem. You should also check the leaves and twigs for a sooty mold that scale insects form.

If you want to remove them, the ideal time is the last few weeks of winter. You may require chemical treatment done by a tree expert for getting rid of scale insects if the outbreak is severe. But keep in mind that chemical treatments can also kill other bugs that feed on scale insects.

In case scale insects are young, you can spray soapy water on the affected areas or the entire tree for the removal of these insects.

If you want to prevent the infestation of scale insects, encourage the growth of predatory insects like ladybugs in your yard as they will feed on most insects and keep your trees and landscape safe. Moreover, keep your tree healthy because scale insects attack weak trees.

Emerald Ash Borer

They specifically attack ash trees and are responsible for killing millions of ash trees every year. The infestation of emerald ash borers is difficult to detect and this is the reason they are so deadly for ash trees. Mostly, the signs of infestation appear after two or more years of these bugs entering the tree.

Emerald ash borers reside in the sot of the tree that flows water and nutrients. They use the vascular tissues as food and directly affect the nutrient supply of the tree causing weakening.

Check your tree for feeding galleries formed in an “S” shape. These galleries have sawdust and frass. Moreover, on the bark, look for holes in the shape of a “D”. However, the holes are usually 1/8 inches only and difficult to spot.

An easier sign of an emerald ash borer attack is yellowing foliage, but it is a sign of the infestation of many other types of insects and pests as well. So, if you see yellowing foliage, consult an arborist.

Weevils

They are another kind of wood borers that are difficult to spot because they are invisible-to-the-eye tiny. The part of the tree they reside in is the base. But by digging tunnels from the tree’s bark, they access the roots of the trees. Strawberry, grape, holly, and azalea trees are usually attacked by weevils.

They infest trees, but they can invade your home as well so you should carry out monthly inspections of your tree to look for signs of weevil infestation. You should look for notched and yellowed leaves. If the attack is severe, they can consume entire leaves and only the veins of the leaves will be left which will hint that you should act immediately for stopping these bugs.

For removing weevils, you can get help from nematodes. They are small worms that are harmless to useful insects, pets, and humans, but they feed on weevil larvae. You can apply nematodes where weevils are present anytime from early spring to fall.

However, if the weevils are adults, you should consider chemical insecticides or consult an arborist.

Conclusion

Pest infestations damage or kill a tree if you don’t spot them early on. If you suspect that your tree is infested or severely damaged by a pest, contact tree removal companies Potomac for cutting the tree down to prevent the spread of the pests.

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