Browntail Moth Update!

Here’s the latest Browntail Moth Update from the Maine Dept. of Agriculture, Conservation & Forestry:

June 10, 2022

The rain we’ve had on and off this past week is a welcome sight for farmers and residents living in browntail-infested areas alike. The precipitation has undoubtedly helped the development of diseases in the browntail caterpillars. This week we are pleased to report we observed at least some fungus-caused mortality at all of our monitoring sites. At a few sites, it wasn’t easy to find live caterpillars to take measurements from, although we did find some after looking on trees a short walk down the road.

Both staff and members of the public have noticed the effects of this disease activity in some of the areas predicted to be hardest hit by browntail moth. Some areas where trees had many webs this past winter do not have the expected severe canopy defoliation. Many things can contribute to this, including the pathogen activity observed last fall on some young caterpillars and additional caterpillar disease development fostered by a combination of precipitation this spring, high browntail populations, and existing disease inoculum primed for an outbreak in the right conditions. As stated last week, some areas outside and even within this area of reprieve show the expected severe canopy defoliation. We again caution that pockets of disease impact may be isolated and might not have spread to your particular location. We’re not out of the woods yet.

Oaks north of Augusta displaying expected canopy defoliation.

Two fungus killed caterpillars in Turner, ME.

Fungus killed caterpillar producing spores that will come into contact with other caterpillars in Augusta, ME.

Contact 211 Maine for answers to frequently asked questions on browntail moths:

• Dial 211 (or 207-874-2211)

• Text your zip code to 898-211

For more info from Maine DACF, visit their web page dedicated browntail moths here.