I don’t live with winter moths, happily, so this is just a general comment about caterpillar pests. I have lived in central NH for more than 40 years. When I first moved here, the Gypsy moths were awful, stripping trees, sometimes several times in successive years which killed them. I can remember going outside and hearing frass sounding like rain because there were so many caterpillars, and getting their webs tangled in my hair as they dropped off the roof edge over the door. I think we went through 2 cycles in my first 15 years here, with the population getting increasingly worse, and then certain fungal diseases killing them back and then repeating. But though I see a few every year now, I don’t think that I have seen a bad outbreak for something like 25 years. I am assuming that diseases and predators (though gypsy moths aren’t native) have come to some type of balance that keeps the population in check under most conditions.

I hope that your winter moths reach some type of equilibrium between the winter moths and their predators and diseases that will keep them under control.

At our previous house, we had several maple trees edging a small back yard. The frass sounding like rain, the caterpillars ballooning down into your hair, the clothing checks when you came in to remove any strays--yep! Kept us mostly inside from late April to late May. (I remember when I learned that tiny black balls that kept landing on my book were caterpillar poop.) They were never quite as good at defoliating as gypsy moths--I saw an outbreak of those in Plymouth a few years ago that was absolutely horrifying--but I'm very glad they seem to be gone from our area for now.

Interesting update in the latest UMass landscape message:

• Winter Moth: (Operophtera brumata) data since 2017 has indicated that the winter moth population in eastern Massachusetts has been on the decline while the percent of winter moth pupae parasitized by Cyzenis albicans has increased! This is excellent news, as it is data supporting the evidence that winter moth populations have decreased while the parasitic fly, C. albicans, has become established at many locations in New England. Dr. Joseph Elkinton’s laboratory at UMass Amherst has released this biological control of winter moth since 2005 and conducted the rigorous sampling required to determine where the insect has established and what its impact on the winter moth population has been at multiple sites in eastern MA. More information about the Elkinton Lab’s research and the biological control of winter moth can be found here:https://www.fs.fed.us/foresthealth/technology/pdfs/FHAAST-2018-03_Biology_Control_Winter-Moth.pdf

The take-home point? Do not worry about winter moth this spring! In fact, management of this insect in landscaped settings will likely not be necessary in most locations. In recent years, it is worth-while to note that some areas on the Cape and other locations in eastern MA have reported noticeable cankerworm populations in the spring, which are often confused for winter moth. Read more about cankerworms in the spring scouting list below.