How to identify and get rid of striped oakworms

If you've noticed more oak leaves on the ground than on the branches lately, it might be time to check for oakworms. These caterpillars can quickly become a homeowner's headache if their population goes unchecked.

Oakworms, particularly active from late summer through fall, can strip an oak tree of its foliage, leading to stress and potential long-term damage to the tree. Initially, it might just be a few nibbled leaves, but as the season progresses, whole branches may become skeletonized, stripped of foliage. This rapid defoliation is often the first visible sign of an oakworm infestation, leaving trees stressed and vulnerable to other environmental pressures.

Oakworms are a part of the silk moth family, which includes giant luna or cecropia moths. The two most common and destructive oakworm species are the orange-striped and pink-striped oakworms.

The caterpillars often clump together as they feed on oak leaves. Since they are more active in the later summer months, they tend not to damage the trees much. However, a large infestation can make many branches bare.

Oakworms can be identified by their green bodies adorned with yellowish-orange or pink stripes. They will also have two spiked horns near the back of their heads when they are older.

Adults are usually furry-looking with a silvery-white dot on each wing. They are a combination of yellow and pink.

A common sign of an oakworm infestation is the rapid defoliation of oak trees, often accompanied by frass (caterpillar droppings) beneath the tree.

How big are striped oakworms?

Oakworms grow up to 1 inch in length.

They are found primarily throughout the eastern United States, wherever oak trees are prevalent.

Striped oakworms are rarely a big problem for most homeowners. However, it may be time to take action if you notice them in large amounts on your oak trees.

Here are a few steps you can take:

• Manual Removal: Pick off caterpillars by hand and drop them into soapy water.
• Water Spray: Use a strong water jet to dislodge caterpillars from tree branches.
• Encourage Natural Predators: Birds and predatory insects can help control the population.
• Tree Health Management: Keep trees healthy and well-watered to withstand and recover from damage.
• Prune: Remove heavily infested branches and dispose of them.