GREEN COVE SPRINGS – Imagine your surprise to find branches of your trees laying in your yard, cut perfectly in a straight line. While you may think it looks like a neighbor pruned some branches, it is in fact an insect trying to ensure its eggs and offspring for the next year.

The Twig Girdler
Twig girdlers (Oncideres cingulata) are grayish-brown long horned beetles that are fairly common to our area and are rarely noticed outside of the fall. This is because the adult females of the species lay their eggs into pencil sized branches on many hardwood trees and then cut a complete circle around that stem. This effectively kills the tip of the branch with the eggs inside and the wind or the weight of the branch breaks it off of the tree.
Once this branch reaches the ground, it will stay there throughout the winter and then the eggs will hatch and the larvae of the beetle will feed upon that branch until it is time to pupate and emerge as an adult to begin the process again. This occurs once a year, every year.
Overall, this is not a major problem for large trees as the loss of a few small branch tips has little effect on the specimen but if twigs are girdled on saplings, seedlings, or young transplants it can cause stunting or malformation. It should also be noted that this damage can also occur on some fruit trees.

Control
Control for the twig girdlers is usually very easy for most homeowners and should involve picking up any fallen, girdled branches or those remaining in the specimen from around trees in the landscape or in surrounding wooded areas. These should be collected and placed in a trash bag for disposal, put in a hot, dry area, or burned where allowed by ordinances to kill the eggs and larvae. After a few years, the total number of beetles should decrease.
It is not necessary to conduct any insecticidal control unless in extreme situations or commercial settings.
If you have any questions about gardening in Florida, call the UF/IFAS Clay County Extension Office at (904)284-6355. Also, visit our website at clay.ifas.ufl.edu and follow us on Facebook.