Clearwing moth larvae are known for boring into trees, where they tunnel through the inner bark and feed on the tissues responsible for transporting water and nutrients. These larvae typically go unnoticed at first, as they work beneath the surface of the bark, disrupting the tree’s vital functions over time.

As the larvae feed, they cause significant damage to the tree’s food- and water-conducting tissues. This results in rough, gnarled bark and contributes to overall tree stress or decline. Prolonged infestations can weaken the tree’s natural defenses, making it more vulnerable to secondary pests, infections, and diseases.

Although treatments can help reduce additional damage, they cannot undo the harm already caused by clearwing moth larvae. Once a tree’s internal tissues are compromised, that damage is not reversible. The success of treatment may depend on the tree’s overall health—trees already in significant decline or under severe stress may not respond well. If a tree continues to deteriorate despite treatment, removal may be the best option to protect nearby healthy trees from further infestation.

Treatment is generally recommended as a short-term control option to help reduce the population of adult clearwing moths, particularly when they are observed crawling or emerging near previously unaffected trees. This is especially important to prevent the spread of infestation to healthy trees. Adult moths are typically active during two key periods: from October to November and again from February through May.

We commonly manage Clearwing moth on both Sycamore and Oak trees, as shown in the photos above. Regular monitoring and timely care are essential—contact us today to protect your trees and preserve your landscape.