Caterpillar or the Winter Moth

For those of you who remember the Gypsy Moth infestation of the early 1980s, we may be facing a similar onslaught this spring, this time from the Winter Moth. Parts of New England, especially along the coast, already experienced extensive defoliation last year, and indications are that they will spread.

The culprit is the larva (caterpillar) of the Operophtera brumata, known as the Winter Moth. Native to Europe, it has gradually been working its way down from Nova Scotia where it seems to have first appeared around here.

The eggs hatch just about now, when daily temperatures average in the 50s. Younger larvae will tunnel into leaf and flower buds and feed on those. As they get older, they begin to feed on the foliage. They can cause extensive damage to oak, maple, ash, apple, crabapple, blueberry, cherry, and ash trees.

Rhode Island officials are experimenting with the introduction of a parasitic mosquito as a form of control.
There are some sprays available to apply when clusters of eggs appear to prevent them from hatching. Once they have hatched and the young larvae are feeding, then application of the bacterium Bacillus thurigiensis has proven to be effective.