Many homeowners assume that fallen limbs and branches from their oak trees are the result of normal aging. When trees age, they have a tendency to lose some of their limbs.
However, another possible cause is twig girdlers. While twig girdlers were rampant during the early to mid-1990s, they are still found in countless landscapes throughout North America.
So, how do you know if twig girdlers are to blame for fallen oak limbs in your landscape?
What Are Twig Girdlers?
Twig girdlers are small longhorned beetles measuring just one-half to three-quarters of an inch long. Like other longhorned beetles, they have incredibly long antennas – usually measuring roughly the same length as their body.
You might be surprised to learn that adult twig girdlers are harmless to oak trees. Rather, it’s the larvae with which you should be aware.
As larvae, twig girdlers will feast on the organic matter within tree limbs and branches, working their way outward to the tips of the limbs and branches.
As these small but destructive beetles feast on a limb or branch, it creates a hollow interior while subsequently causing the limb or branch to drop.
How to Spot a Twig Girdler Infestation in Oak Trees
A telltale sign of a twig girdler infestation is the presence of fallen limbs and branches with a hollow interior. Don’t assume that all fallen limbs or branches are the result of an infestation.
Rather, you should only be concerned if the limbs or branches are hollow.
If an oak tree is infested with twig girdlers, you may also discover sloughing bark.
When trig girdlers begin to consume the organic matter within the tree’s limbs and branches, the tree will shed some of its bark due to increased stress.
Protecting Your Oak Trees From Twig Girdlers
There are a few steps you can take to protect your oak trees from twig girdlers, one of which is to remove the affected limbs or branches.
If you discover some limbs or branches on an oak tree that are hollow but haven’t fallen yet, cut them down. Allowing them to stay on your oak tree will only allow the twig girdlers to reproduce and spread elsewhere.
There are also insecticides available that can treat and prevent twig girdler infestations.
Talk to a professional arborist or landscaping company for more information on which insecticide product is right for your oak trees.
Keep in mind that twig girlders can affect other types of trees besides oak.
While oak trees are one of the most common species targeted by these destructive beetles, they will feast on other trees like poplar, dogwood, hackberry and more.
If we can help with any of your tree care needs give us a call at 512-846-2535 or 512-940-0799 or