Oak wilt experts from Rockoff Tree Solutions identify the disease as one of the worst threats to trees in Texas. It’s tricky to diagnose and can kill healthy trees in six months or less. So, as an early response is the best way to limit the damage, the next question is, “What does oak wilt look like?”
Read on and determine whether it’s time to call in a professional arborist.
What Is Oak Wilt?
This contagious tree disease destroys the xylem vessels within trees. These water-conducting veins play an essential role in keeping your tree oak alive. As the infection spreads, leaves wilt and die off.
What Causes the Disease?
The infection occurs when Ceratocystis fagacearum, a fungus, gains a foothold in live oak.
Watch Out for the Following Signs
While a formal diagnosis depends on laboratory results, infected trees may show differing symptoms. The answer to “What does oak wilt look like?” is, therefore, dependent on the species of oak.
For example, bur oaks lose a few leaves at a time in summer. The effect on red oaks, however, can be more devastating. They may lose nine out of ten leaves in under a month.
The most common signs are:
- Leaf wilt characterized by a bronzing or lightening of leaves
- Water soaking, characterized by leaves turning dark green
- Leaf necrosis, characterized by brown veining
- Defoliation that differs depending on the species but typically begins at the canopy’s outer edge and works its way in
- The formation of pressure and fungal mats that smell like fruit or wine
- The cracking of the bark near the pressure mats
- Brown streaking below the affected branches
Many of these signs may also indicate less harmful infections, so only lab tests can give a definitive diagnosis.
Which Species Are Most at Risk?
All oaks are at risk, but red oaks are the most likely to develop fungal mats. White oaks fare better, but live oaks are the most resistant. Despite this, observe live oaks as the disease can spread quickly through their root systems rather than fungal mats.
How Does the Disease Spread?
The disease spreads through fungal spores, direct contact, or infected root systems. Fungal mats forming on red oaks are particularly attractive to insects, which eat the spores and spread the fungus to healthy trees.
Infection through the roots is even more insidious because there is no need for third-party involvement. A root grafting can infect new wood or travel through the xylem. The disease can spread as far as 150 feet from the initial site within 12 months.
Finally, the infection can spread from a woodpile to a healthy tree.
The Prevention and Treatment of Oak Wilt
Calling in a certified arborist in the early stages is essential to halt the contagion. An expert will recognize the symptoms and send samples to the lab. From there, they can formulate a plan of action to stop the spread and prevent reinfection.
They are likely to adopt a many-pronged approach that may include:
- Preventing new infections by minimizing the risk factors
- Removing infected wood and trees as necessary
- Trenching to isolate infected roots
- Using a fungicide
- Boosting the health of existing trees
- Planting species that are better able to defend themselves against infection
- Creating more diversity in the species of trees on your property
Do You Believe You See Signs of Oak Wilt?
Find out for sure by calling in certified arborists from Rockoff Tree Solutions at 830-955-0304. With almost 30 years of industry experience, they’re the best team to answer, “What does oak wilt look like?”