How to Protect Oak Trees from Oak Wilt

Date January 12, 2022


Author TreeNewal Staff

One of the most well-known tree genuses is the mighty oak tree, with its massive crown and hearty branches – their lifespan can be as long as 1000 years! But being big and tough doesn’t mean they aren’t still prone to a pesky affliction known as oak wilt. Here’s all you need to know about oak wilt protection to keep your beautiful oaks safe and healthy!

What is oak wilt

Oak wilt, or Ceratocystis fagacearum, is a fungal disease that affects the oak tree’s vascular system. The fungus is spread by small sap beetles hungry for tasty, fresh wounds on the trees, picking up the spore from the infected tree and carrying them to the already damaged uninfected. Storm damage, tree trimming cuts, weed whips, and the like are common causes for these vulnerable wounds, and with such direct access to internal systems through those wounds, it can take as little as 15 minutes for the infection to take root in the oak tree.

Once oak wilt spores spread inside the fresh wound, the tree attempts to plug up cells to fight off the disease, leading to the telltale wilt. Though less common, the disease can spread via root grafts, which is another strong reason an infected tree is such a risk to nearby trees as well.

The trees at greatest risk of dying from oak wilt disease are those in the red oak family: northern pin, northern red, black oak, and the red oak itself. At the other end, those most likely to survive such an infection are of the white oak family: swamp white, bur oak, English oak, and again, the white oak itself.

How to identify oak wilt

The classic sign of oak wilt is rapid discoloration and wilting of leaves in a tree. It starts with subtle green-ish color shifts often visible towards the very top of the tree crown. Particularly here in Texas, you will often see the development of yellowing veins that gradually turn brown on the native live oaks before they rapidly fall from their branches. With red oaks, the younger leaves indicate wilting and as they become a pale green and ultimately brown, while older foliage turns a dark shade of green or even bronze.

Some of these signs and color shifts can be very subtle and appear to be other types of infections. For how pervasive and quickly oak wilt can spread, it’s deeply important to make sure that this disease is diagnosed correctly. If you have any suspicion of trouble, make sure you call on professional tree care services like TreeNewal as early as possible to get you the most accurate identification and treatment plan.

How to prevent oak wilt

The best way to prevent a problem is to plan plan plan! Help prevent the spreading of oak wilt by avoiding pruning at-risk trees during their growing season. The peak of sap beetle populations coincides with this season, and any open injuries to a tree can immediately be highly attractive to those hungry beetles. Ideally, February to November will be pruning-free, but if that’s not possible for you, at the very least, keep your oak trees protected by avoiding pruning during the months of March to mid-July. In other words, the rule of thumb advises no pruning from just before buds begin to break until the leaves begin to fall again for the season’s changing naturally.

Sometimes all the prevention still isn’t enough, and accidents happen. If your tree does end up with a fresh injury, a swift and light application of wound dressing is likely your best bet in keeping your tree protected during those especially vulnerable months.

How to control oak wilt

So, now that TreeNewal has come out to diagnose your tree with oak wilt officially, there are admittedly limited options to treat oak wilt in your unlucky oak tree. But take heart! We can apply treatment to the nearby trees to help control the spread of oak wilt. Systemic fungicides can be injected into a tree’s trunk to stop the fungal spores in their tracks before making their way through the underground root graft matrix.

If you need advice or assistance with preventing, identifying, or managing oak wilt in your oaks, get in touch with our TX Oak Wilt Qualified Arborists at TreeNewal and enjoy tailored tree care advice.


To learn more about How to Protect Oak Trees from Oak Wilt, call our Argyle and Southlake-based teams

at tel:(817) 592-6846 or send us a message.

We’re a little different than the average tree services company.

Learn more about TreeNewal’s ISA Certified Arborists!

Our Dallas/Fort Worth-based tree doctors can explain how sustainable tree care services add more value to your bottom line.

Healthy trees, healthy lives.