Large Bugs in Oak Trees

• Oak tree.Paul Edmondson/Digital Vision/Getty Images
  
  The oak trees that bring shade and larger-than-life visual impact to your home landscape are under threat of invasion by large bugs. Prone to a variety of pest problems, oak trees kept vigorous and free of damage have a greater capacity for avoiding and recovering from large pests that often bore into wood, leaving extensive damage in their wake.
  
  

Orangestriped Oakworm

• Orangestriped oakworms (Anisota senatoria) are common pests of the oak tree, according to the Clemson University Extension. These large bugs measure a mature length of 2 3/16 inches with bodies in black with orange or yellow stripes. Due to heavy feeding on tree leaves, oaks often experience complete defoliation. While this damage is not problematic if oakworms are controlled, neglecting an infestation for several years results in decline. To control orangestriped oakworms, mild problems are solved through hand-removal. For extreme infestations, reliable chemical control includes pesticides with the active ingredient bifenthrin, permethrin or acephate.
  
  

Red Oak Borer

• Red oak borers (Enaphalodes Rufulus) are long-horned beetles that act as large bug pests on oak trees. Measuring up to 1 3/8 inch in length, the length of antennae surpass the length of the body. Adult beetles display bodies in a light brown hue. The larval borers, however, create the greatest damage, measuring 1 1/4 inch in length with the exhibit of white bodies. Boring into wood, red oak borer larvae create tunnels with diameters that measure up to 2 1/2 inches. Severe damage can lead to plant death, particularly on already stressed or weakened trees, according to the Arkansas Forestry Commission. For control, chemical options do not offer support. However, management is possible through consistent care, extra watering during times of drought and pruning every few years.
  
  

Red-Headed Ash Borer

• Red-headed ash borers (Neoclytus acuminatus) are referred to as long-horned beetles in their adult form and and round-headed borers in their larval stage. As their name implies, adults display prominent antennae as well as large bodies that mature from a larval length of approximately 3 1/4 inches. Red-headed ash borers exhibit bodies in a combination of red and light brown hues with yellow stripes. Commonly infesting oak trees, this large bug typically attacks stressed, weakened and wounded trees upon which larvae feed beneath bark, tunnel into heartwood and then emerge as adults. Their boring causes extensive damage and diminished health. For control of these bugs, growers should prune and remove dead or damaged plant parts including fallen debris and avoid creating wounds through which bugs invade. For chemical management, insecticides with the active ingredient chlorpyrifos offer control.