What Bugs Are Eating My Tree’s Leaves?

While environmental stress or disease can certainly cause leaf issues, one of the most common, and often most visible, causes of damage is insect activity. When bugs begin chewing holes through your tree’s leaves, the damage can escalate quickly. This is because the insects weaken a tree’s ability to photosynthesize and make it more vulnerable to drought, disease, and storm damage. The best way to stop the decline is to understand which insects might be responsible and take action right away.

Signs Bugs Are Eating Your Tree’s Leaves

Are your trees being eaten alive? Here are some top signs that your favorite woody plants are being targeted by leaf-eating insects:

Chewed or Ragged Leaf Edges

One of the earliest signs of insect feeding is irregular leaf margins. If the edges appear scalloped, notched, or uneven, chewing insects such as caterpillars or beetles may be stripping away tissue. While this may seem like a cosmetic issue at first blush, when entire sections of the canopy take on a ragged appearance, the tree is losing far more energy than it can afford.

Holes in the Leaves

Small, round holes often point to beetles, while larger, irregular holes may indicate caterpillars or sawflies. Some insects even feed from the inside out, leaving “shot-hole” patterns where tissue between veins disappears first. These holes create a telltale pattern that helps narrow down the specific leaf-eating pest.

Browning, Curling, or Distorted Leaves

Not all insects chew leaves; some pierce the tissue and feed on the sap. Aphids, leafhoppers, scales, and mites are particularly known for injecting toxins or extracting nutrients, leading to curling, yellowing, or misshapen leaves. This damage often appears on new growth first.

Webbing or Silky Tents

Silky nests woven between branches or stretched across foliage commonly indicate caterpillars such as fall webworms or eastern tent caterpillars. Spider mites also leave fine webbing, though usually on the underside of leaves. While webbing isn’t a direct sign of feeding, it does indicate the presence of leaf-eaters.

Visible Insects, Eggs, or Frass

Sometimes, the evidence is unmistakable: clusters of larvae, beetles swarming foliage, or droppings (frass) collecting beneath the canopy. Be sure to also flip leaves over to check for eggs or larvae, as many insects prefer the more protected underside of leaves.

Common Leaf-Eating Insects in North Carolina Trees

North Carolina’s climate supports a wide variety of insects, and while many are harmless, some can cause extensive damage. Here are the pests most commonly responsible for chewed leaves in the Charlotte, Lake Norman, and Asheville regions.

Caterpillars (Including Webworms & Tent Caterpillars)

Caterpillars are among the most aggressive leaf eaters, and two of the most common in NC are eastern tent caterpillars and fall webworms. Eastern tent caterpillars create noticeable silk tents in early spring and devour leaves on cherries, apples, crabapples, and other ornamental trees. Fall webworms appear later in the season and enclose entire branches in dense webs.

Most caterpillars feed from the leaf edge inward, leaving ragged gaps or even completely stripping branches. Large populations can defoliate a tree in days, putting tremendous stress on its energy reserves.

Japanese Beetles

These shiny green and copper beetles feed heavily on summer foliage, often leaving a “lace-like” skeleton behind. They consume everything except the leaf veins and typically feed in groups, turning a formerly lush tree canopy transparent almost overnight.

Japanese beetles are especially fond of:

• Birch
• Linden
• Crepe myrtle
• Roses
• Fruit trees

Their rapid feeding habits make early intervention essential.

Aphids

Aphids cluster on the undersides of leaves and suck sap from tender growth. This feeding causes leaves to curl, twist, or turn yellow. You may also notice a sticky residue (known as honeydew) left behind on the leaves. Aphids secrete this honeydew, which, in time, leads to black sooty mold covering leaves, branches, and even nearby outdoor furniture.

While aphids rarely kill trees outright, they weaken them significantly and pave the way for secondary pests or infections.

Bagworms

Bagworms construct spindle-shaped bags made from silk and pieces of leaves. These bags look like small ornaments hanging from branches and can blend in surprisingly well. Bagworms feed heavily on evergreen trees, but deciduous trees are not immune.

Infestations often go unnoticed until leaves brown or entire limbs begin to thin, at which point populations may already be widespread.

Leafminers

Leafminers feed from inside the leaf, tunneling between layers of tissue and leaving winding trails that look almost artistic. Trees commonly damaged by leafminers include:

• Birch
• Oak
• Boxwood
• Maple

While not always catastrophic, repeated infestations can weaken a tree, year after year. It’s also helpful to note that because they live within the leaf, surface treatments are often ineffective, and targeted trunk injections are needed instead.

Spider Mites

Spider mites are tiny (often no bigger than a dust particle), but their impact can be extensive. They pierce leaf cells, causing stippling (small pale dots), bronzing, or fine webbing across foliage. Hot, dry weather accelerates their reproduction, allowing populations to explode quickly. Left untreated, mites can cause significant leaf drop and long-term stress.

Cankerworms

Also known as inchworms, cankerworms are a significant pest in North Carolina, particularly for oak trees and maples. These small, green or brownish caterpillars move with a distinctive looping motion. You might notice them hanging from trees on silken threads, especially in the spring.

Because cankerworms are chewers, they eat the leaf tissue, leaving behind ragged holes. In years with high populations (outbreak years), they can completely defoliate large canopy trees. While a large oak can survive a year of this, consecutive years of defoliation can lead to decline and death, especially if the tree is also fighting drought or root issues.

Sawflies

Though similar in appearance to caterpillars, sawfly larvae belong to the wasp family and often feed in large groups. They skeletonize leaves, strip entire branches, and can rapidly defoliate certain species such as pines and oaks. Because they feed simultaneously in clusters, sawflies often cause sudden, noticeable damage.

When Leaf Damage Becomes Serious

A few chewed leaves are normal, but when damage continues for multiple seasons or spreads rapidly across the canopy, the tree’s health is at risk. This is because losing leaves year after year (or aggressively in one season) reduces a tree’s ability to produce the energy it needs to grow, defend itself, and recover from environmental stress.

For young or newly planted trees that have limited root systems, the consequences of the insect activity could be even more severe. This is due, in part, to the fact that they do not have the ability to tolerate heavy leaf loss and could eventually suffer from stunted growth or structural issues.

Why You Should Leave Pest Diagnosis & Treatment to Certified Arborists

Correctly identifying the insect attacking your tree is key to controlling it. Many species cause similar damage, and misidentification often leads to ineffective treatments that allow the problem to grow.

Certified arborists from Heartwood Tree Care:

• Use trained diagnostic techniques to pinpoint the exact pest.
• Understand seasonal insect behavior and treatment timing.
• Apply targeted solutions that avoid harming beneficial insects.
• Can prune, treat, or perform canopy work safely.

Remember, trying to climb trees, spray chemicals, or remove infested branches without proper training can be dangerous. A professional ensures the job is done safely and effectively.

Get Professional Treatment for Leaf-Eating Insects in NC

Trees deal with countless stressors throughout their lives, and insect damage is just one of the challenges they face. While many infestations can be caught early and managed through proper pruning, seasonal tree spraying, or plant health care programs, some cases lead to significant decline. If a tree becomes too compromised, our arborists can remove it safely.

In some cases, insects only cause inconsequential visual damage that bothers us more than the trees. If this is the case, you may not need to do anything. Of course, you should always talk to your arborist first.

Are insects chewing through your tree’s leaves in Charlotte, Lake Norman, or Asheville, NC? Count on Heartwood Tree Care for expert diagnosis and effective treatment solutions. Contact us today to protect the health and beauty of your trees.