Winter Moth Alert!

Spring is here and everything seems to be growing! As perennials pop up and the trees start producing leaves, most people tend to assume that the plants in their landscape are doing just fine. Truth be told, most of them probably are growing well without assistance. But on Cape Cod, people may not realize that their trees are actually being eaten.

Right now the winter moth larvae are chomping on maples, cherries, birch and apple trees. Once the oaks leaf out they’ll attack those as well. Right not these green caterpillars are tiny, so they’re making little holes. But as they grow they’ll be eating more so it’s best to start protecting your trees as soon as possible.

Spinosad works very well to control winter moth larvae damage. We stock Captain Jack’s Dead Bug Brew, with the active ingredient of Spinosad.

Use it on any of the trees listed above, and on roses, Hosta and Heuchera. If your tree is blooming, use Bt (Thuricide) instead because wet Spinosad isn’t good for foraging bees. (Spinosad is fine once dry – it’s just not good to hit bees with the wet product.) Spray once now and again as leaves grow larger. You may need to spray vulnerable trees three times between the beginning of May and mid-June.

For more information, download this Winter moth overview handout from the UMass Extension.