Pests That Can Kill Trees


There are a lot of pests capable of attacking hardwood trees. These attacks can sometimes lead to the destruction or ultimate death of trees in your yard, to the point where cutting them down is the only solution. The pests (mostly insects) are usually invasive species, which means they aren’t native to the area and therefore don’t have natural predators here. In fact, their effect can be so vast and powerful that it can be responsible for large scale deforestation.

It is important for farmers, gardeners, horticulturists and the general public to learn to recognize the signs of invading insects so that their invasion can be tackled early, before it becomes too late.


There are two main ways in which insects can cause harm to a tree. The first is by causing direct injury to the plant, which happens when the insects feed on the leaves and burrow into stems, fruits and roots. The second way this happens is through indirect damage in which the insect does not cause a lot of physical damage, but rather transmits a bacterial, viral or fungal infection to the tree. Most of these insects are known to multiply rapidly and finally dominate the plant.

Invasive insects usually possess appendages adapted for boring. They are capable of creating tunnels in tree trunks to feed under the bark of living wood, thereby destroying tissues in plant that help to conduct water and sap. This can ultimately cause girdling, branch dieback and weakness of the plant structure.



This invasive insect can also be referred to as the sky beetle. It was accidentally introduced into America from China and Korea from wood packaging materials.

Description: They have shiny black backs with about 20 small white spots scattered all over each of the wings. The antennae are also black and white. They are capable of flight, but only for short distances.

Detecting an invasion: The Asian Longhorned Beetle is known to attack a variety of trees species, including poplar, willow, sycamore and horse chestnut, but its favorite hosts are maple trees. Tree invasion can be detected in the form of small holes occurring at larger branches of the crowns of infested trees. Sap can be seen oozing out of this hole to the bark of the infected tree. The presence of dying branches and yellow leaves in the absence of drought can also signify the presence of the insect.


This bug has become one of the most persistent and notorious in America. It was accidentally introduced into America with the first specimen collected in 1998.

Description: The stink bug has a mottled-brown color with a shield-shaped back. Its legs and antennae are white and brow with alternating black and white pattern along the abdomen. The adults are mostly active from April to early May.

Detecting an invasion- An invasion can be detected in the formation of dimpled or necrotic areas on the outer surfaces of fruits or plants, leaf stippling and seed loss. The Brown Marmorated Stink Bug is a sucking insect. It mostly makes use of its proboscis to pierce the host plant and feed on it. It is known to attack tree fruits, legumes, vegetables and ornamental plants.


The emerald ash borer, also known as the jewel beetle, is a species that originated from eastern Asia. Outside of its native area, it is known to cause significant damage to ash trees.

Description- The adult borers have a metallic green color with a length of 0.30 inches. The larva possesses a worm-like shape.

Detecting and invasion- The invasion of ash borers can be detected with the presence of D-shaped holes all over the bark of a tree. The adult borers are known to drill D-shaped holes in trees to enable them to exit their chamber.

The ash borers can cause damage to ash species, including green ash, black ash, white ash and blue ash. The adults feed on the foliage of these ash trees and the larvae are more likely to create tunnels in tree trunks and feed on the bark, thereby disrupting the flow of water and nutrients to the tree.


  1. Homeowners should first educate themselves to be able to identify the harmful species among their trees.
  2. Encourage and facilitate the growth of healthy trees so that they can naturally fend off pests.
  3. Make use of oil sprays to smother soft-bodied insects such as aphids and clog their breathing pores.


It is important that you keep an eye out for these pests yourself, but hiring a professional is the best bet when it comes to securing the health of your tree. There is a vast variety of tree pests in Michigan, and some like the Emerald Ash Borer cause terrible outbreaks. It may take a trained professional to help you get rid of the next invasion in your farm or garden. We can easily identify the signs and find the necessary steps to take in solving the problem. Contact us today for assistance.