Identifying and Treating Common Central Virginia Tree Diseases

Living in Virginia, you’ve likely noticed how much our communities value our trees. The shade, beauty, and environmental benefits they provide make it worth investing time and effort into their care.

Unfortunately, even with the best care, trees can fall victim to various diseases. The common Central Virginia tree diseases discussed in this article can significantly impact your trees’ health and appearance, potentially reducing their lifespan or even killing them.

Let’s dive in and learn how to protect our trees and urban forests.

Key Takeaways:

• There are 5 tree diseases prevalent in Central Virginia right now, including laurel wilt, thousand cankers disease, anthracnose, beech leaf disease, and powdery mildew.
• Not all tree diseases have cures, which makes spotting the symptoms of each disease important in helping prevent other trees from becoming infected.
• Proper watering, pruning, inspections, and fertilization strengthen trees and make them less susceptible to disease.

5 Tree Diseases You Should Watch Out For

Trees, like any living organism, are susceptible to a variety of diseases that can weaken, disfigure, or kill them. Being aware of the most common tree diseases in Central Virginia is the first step in protecting them. Here are six diseases that we frequently come across in our area.

1. Laurel Wilt

Laurel wilt is a devastating disease that primarily targets plant species in the Lauraceae family, like redbay, sassafras, and spicebush trees.

It is caused by a fungus spread by the redbay ambrosia beetle that often hitchhikes to new areas by hiding in infested firewood. The beetle carrying the fungus bores into the plant tissue of a healthy tree and infects the tree’s vascular system, preventing the flow of water and nutrients.

Signs and Symptoms

Symptoms of laurel wilt often appear suddenly and include:

• Wilting and browning leaves
• Change in appearance starting at the top of the tree and progressing downward
• Dark discoloration of the wood beneath the bark
• Strings of sawdust the redbay ambrosia beetles leave behind when boring into a tree

Laurel Wilt Treatment

Unfortunately, there is currently no cure for laurel wilt. Once the tree is infected, it will eventually die. To prevent the spread of this disease, infected trees must be removed and destroyed.

2. Thousand Cankers Disease

Thousand Cankers Disease (TCD) is a destructible disease that is solely responsible for the extensive dieback and mortality of black walnut trees across the country. It is caused by a tag team of a tiny bark beetle and a fungus. The beetle depends on the fungus for food and then carries the fungus to a healthy tree, where it infects and eventually blocks the transport of water and nutrients.

Signs and Symptoms

During the early stages of TCD, symptoms are pretty subtle and hard to spot because the cankers are concealed under the bark, and the beetle entrance and exit holes are small. However, you can still inspect your trees for:

• Sudden wilting of healthy leaves
• Branch dieback from the top down
• Small cankers on branches and trunk

Thousand Cankers Disease Treatment

There is no treatment currently effective against thousand cankers disease. To slow its spread, it is important to remove and destroy trees as soon as possible.

3. Anthracnose

Anthracnose is a common fungal disease that affects a wide range of tree species, but the most common in Virginia are sycamore, white oak, elm, dogwood, and maple.

Anthracnose fungi overwinter in infected leaves and twigs on the ground. In the wet conditions of spring, the spores spread rapidly, carried by wind and splashes to the buds and young leaves of trees.

Signs and Symptoms

Anthracnose symptoms vary depending on the tree species affected. Common symptoms include:

• Dark, irregular leaf spots
• Leaf browning and curling
• Premature leaf drop
• Abnormal mass of twigs known as witches’ broom

Anthracnose Treatment

While anthracnose rarely kills mature trees, it can weaken them and make them more susceptible to other diseases and pests. However, systemic fungicides can effectively treat this disease.

4. Beech Leaf Disease

Beech leaf disease is a relatively new disease caused by a microscopic roundworm known as a nematode. The nematode enters the tree’s leaf buds in the fall and spends the winter multiplying inside. The damage done over winter is present in the leaves when they expand in the spring. As the disease progresses, the tree will quit producing leaves and eventually die.

Signs and Symptoms

The most noticeable symptom of beech leaf disease is the dark bands appearing between the leaf veins. Other symptoms include:

• Leaf curling and distortion
• Reduced leaf production
• Thinning canopy

Beech Leaf Disease Treatment

Unfortunately, beech leaf disease is 100% fatal – with most seedlings and saplings dying in one to three years and mature trees dying in three to ten years. Research is ongoing to better understand the disease and develop effective treatments.

5. Powdery Mildew

Powdery mildew is a common fungal disease affecting various plants, including many trees in our backyards. This disease steals nutrients from the plant, stunting its growth.

The worst part is that powdery mildew spreads like a rumor in high school – fast and sneaky! It thrives in warm, dry conditions but needs high humidity to form new spores. This disease hates both extreme and heavy rain, so it’s most likely to attack trees in crowded, shady spots with poor air circulation.

Signs and Symptoms

While the most obvious sign is the white, powdery coating on the leaves, other symptoms include:

• Leaf curling and distortion
• Stunted growth

Powdery Mildew Treatment

The good news is that there are a few ways to help control powdery mildew. Pruning or spacing your trees appropriately can improve air circulation around them. Choosing planting locations with ample sunlight can also deter this fungus. Using fungicides specifically designed for powdery mildew may be necessary for more severe cases.

Help Prevent Tree Disease with Regular Tree Care

There’s a famous saying out there that says the best defense is a good offense, and in this case, the best defense against tree diseases is proper tree care. By providing consistent attention and care, you can significantly reduce the risk of your trees falling victim to these problems. This includes:

• Pruning: Removing dead, diseased, or crossing branches improves air circulation and sunlight penetration, reducing the likelihood of fungal diseases.
• Regular Inspections: Checking your trees for signs of pests, diseases, or damage allows for early intervention and prevents problems from escalating.
• Proper Watering: Consistent, deep watering helps trees develop strong root systems and increases their resilience to diseases. Avoid overwatering, which can create conditions for fungal growth.
• Fertilization: Providing essential nutrients keeps trees healthy. However, fertilization is only recommended if soil or plant foliage tests indicate a deficiency.

Get Expert Help with Common Tree Diseases from Dyer’s Tree Service

If you notice unusual symptoms or have concerns about your trees, don’t hesitate to seek professional help. Dyer’s Tree Service offers expert tree care services throughout Central Virginia, including disease diagnosis and treatment.

Call Dyer’s Tree Service at 540-827-7245 for a comprehensive tree evaluation today.