Tree Diagnostic

Tree Ailments call for a Tree Doctor

If you notice unusual damage to your trees, such as bore holes, mushrooms, sudden leaf death, or bark discoloration, your tree may be plagued by insects or disease. It’s important to look at the symptoms very carefully to get an accurate diagnosis for proper treatment. If ignored, the issue can kill the tree and spread to other trees on your property.

Insects and diseases can become serious threats to your tree’s health. After careful analysis, we can make a reasonable diagnosis of the problem and select the most effective treatment. Our four decades of experience with common insects and diseases allow us to determine the best course of action or treatment for your tree.

Insect Infestation

Some insects can cause injury and damage to trees and shrubs. By defoliating trees or sucking their sap, insects can retard plant growth. By boring into the trunk and branches, they interfere with sap flow and weaken the tree structure. Insects may also carry some plant diseases. In many cases, however, the insect problem is secondary to problems brought on by a stress disorder or pathogen.

It is important to remember that many insects are beneficial rather than destructive. They help with pollination or act as predators of more harmful species. Therefore, killing all insects without regard to their kind and function can actually be detrimental to tree and shrub health.

emerald ash bore beetle
Emerald Ash Bore Beetle

Insects may be divided into three categories according to their method of feeding: chewing, sucking, and boring. Insects from each group have characteristic patterns of damage that will help determine the culprit and the proper treatment.

Chewing insects eat plant tissue such as leaves, flowers, buds, and twigs. The damage by these insects is often seen by uneven or broken margins on the leaves, skeletonization of the leaves, and leaf mining. Chewing insects can be beetle adults or larvae, moth larvae (caterpillars), and many other groups of insects. The damage they cause (leaf notching, leaf mining, leaf skeletonizing, etc.) will help in identifying the pest insect.

Sucking insects insert their beak (proboscis) into the tissues of leaves, twigs, branches, flowers, or fruit and then feed on the plant’s juices. Some examples of sucking insects are aphids, mealybugs, thrips, and leafhoppers. Damage caused by these pests is often indicated by discoloration, drooping, wilting, leaf spots (stippling), honeydew, or general lack of vigor in the affected plant.

Boring insects are a very common problem that can go unnoticed. Often the issue is unnoticed until the damage is extensive. Early diagnosis and annual inspects can reveal these problems and in most cases, stop the damage. All pests in this category spend time feeding somewhere beneath the bark of a tree as larvae. Some borers kill twigs and leaders when adults feed or when eggs hatch into larvae that bore into the stem and develop into adults. Other borers, known as bark beetles, mate at or near the bark surface, and adults lay eggs in tunnels beneath the bark.

Some of the common insects we see infesting trees include: Emerald Ash Borer, Oak Bark Beetle, Pine Bark Beetle, Wooly Adelgid, Aphid, Bag Worms, Spruce Borer, Dogwood Borer.

gypsy moths
Eastern Tent Caterpillars
aphid infestation - tree service
asian longhorn beetle causing tree damagee
Asian Longhorn Beetle
Emerald ash bore beetle damage in wood of tree
Emerald Ash Bore Damage
emerald ash bore beetle exit hole
Emerald Ash Bore Exit Hole
Oak Bark Beetle limb damage in Jarrettsville, MD
Oak Bark Beetle Damage
oak bark beetle damage in branches of tree
Oak Bark Beetle Damage


Three things are required for a disease to develop: the presence of a pathogen (the disease-causing agent), plant susceptibility to that particular pathogen and an environment suitable for disease development.

Plants vary in susceptibility to pathogens. Many disease-prevention programs focus on the use of pathogen-resistant plant varieties. Even if the pathogen is present and a susceptible plant host is available, the proper environmental conditions must be present over the correct period of time for the pathogen to infect the plant.

Common Tree Diseases in Maryland Include:

Oak Wilt

Root Rot

Drought Leaf Scorch

Bacterial Leaf Scorch

Powdery Mildew



Verticillium Wilt

Fire Blight

tree inspection of tree with damaged bark


Trees are not in their natural environment growing in your yard. Additional care is needed to ensure a healthy, stress-free tree. In many cases, fertilization can be the main determining factor to keep insects and disease away. Oftentimes fertilization can be the last line of defense before the tree dies. We can evaluate your trees and discuss their condition, informing you of any recommended treatments.

chemical application of unhealthy tree
chemical application of fertilizer for tree in Towson, MD
chemical application of tree in Cockeysville, MD
chemical application of fertilizer for tree in Fallston, MD


Contact us to request an estimate.