Winter Moth Treatment And Prevention Tips

The winter moths are invasive pests that can strip trees of their leaves at an alarming rate. The larvae (or caterpillars) of these pests feed on the leaves and buds of apple, crabapple trees, maple, white elm, blueberry, oak, and ash. If untreated, the tree can become completely defoliated, ultimately leading to its death. It can cause homeowners and property managers a lot of stress.
Here in this post, we’ll guide you about treatment and prevention related to winter moths.

How to identify winter moths

When newly hatched, the winter moth larvae appear to be pale green caterpillars with white stripes. The male winter moths are light brown to tan in color with four wings. These elongated wings have a slightly hairy or fringed appearance. On the other hand, female winter moths are grey and have tiny scales that give them a furry look. Since they are almost wingless, they cannot fly.

Life cycle

The female winter moth lay a cluster of nearly 150 eggs under tree bark or twigs, where they spend the rest of the winter. During the spring, the eggs hatch into pale green caterpillars and start feeding on the foliage. The caterpillars spin a strand of silk, which disperse them into tree canopies through the air currents. The damage to the tree starts when these caterpillars work their way into the tree buds and leaves to feed. The caterpillars don’t stop and continue to migrate from bud to bud, devouring as much as they can. When feeding ends in mid-June, the caterpillars fall to the ground to pupate and emerge as moths. 
The most visible sign of a heavily infested tree is that it will be completely defoliated. The complete defoliation can reduce the annual growth rate of some oak species and successive defoliations can kill branches or entire trees.


To effectively treat winter moths, you first need to find out what stage the pests are in. After identifying the stage, consider factors like the size of the tree to be treated or proximity of homes. It is also important to begin the treatment early in the year as waiting too long can further deteriorate the problem. 
Non-chemical management
If your tree suffered heavy defoliation, then water is crucial for the tree to have a second flush of leaves. Take a look at these options:

Tree banding
It is a pesticide-free option where you place a sticky band around the tree's trunk in early to mid-November. The sticky band prevents the female moths from crawling up the tree to lay their eggs. The band should be monitored and replaced over the course of a month, as the band becomes full.

Dormant oil
Use dormant horticultural oil from November to January for effective moth prevention. 

Chemical management
Use insecticides containing Spinosad, Indian, or Sevin to treat the newly hatched caterpillars. For feeding caterpillars, homeowners can use DiPel or Biobit, Javelin, and others containing B.t.k., which are applied to leaves that kill them when ingested by the caterpillars.


It is a good idea to prevent these pests from hatching. You can use spray or soil/trunk injection treatments with Spinosads and B.t.k to prevent these caterpillars from hatching.

About Seacoast Tree Care

If you notice a growth of ticks on your plants, contact Seacoast Tree Care. We are experts in complete tree care, preservation, and removal and have a qualified team of certified arborists who will use tick prevention methods to ensure that your trees and plants flourish and thrive in all seasons. Call us at 603-431-0101 or 978-225-6644, or drop an email at info@seacoasttreecare.com to know more. You can also fill up our contact form, and we will get back to you.

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