Wintermoth Caterpillar Alert

The wintermoth caterpillar is an introduced pest to Massachusetts, and has become a significant threat to the health and beauty of most of our deciduous trees. You may have seen this small green inchworm in the spring chewing holes in, or even defoliating, your trees. This pest has no natural controls, so it is free to proliferate, becoming a bigger nuisance each year.

During the next several weeks, you may notice small, pale brown moths gathering around your porchlight, or heading for your headlights as you drive at night. These adult wintermoths will soon lay their eggs, and their brood will hatch next spring and renew the cycle of feeding damage to your trees. They typically feed from mid April through June, at which point they will drop to the soil and pupate until November.
There are a few treatment options available. Foliar tree sprays are the most effective control, during the time of spring feeding, and there are very good organic options. Tree banding now may reduce the number of female moths that are able to successfully lay their eggs on the host tree. There are also microinjection options when spraying is not desirable or practical. Consult your certified arborist for more information. You can also check the following link for a complete data sheet- http://www.umassgreeninfo.org/fact_sheets/defoliators/winter_moth.pdf.

Submitted by;

Jeff Bourque
MA Certified Arborist
Plant Health Care Manager
Mayer Tree Service

978-766-4365
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