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by Dale Finseth
I'm letting my conservation characters take a break this week. It is that time of the season when we want to help people out hiking or even in their back yards to identify invasive forest pests.
Maine's Soil & Water Conservation Districts are working with the Maine Forest Service to help people identify invasive forest pests, i.e. bugs that could do serious damage to our woodlands. While some of those bugs have not yet appeared in Maine, we need to be vigilant and identify them should they appear.
Some are already here. The hemlock woolly adelgid is not that uncommon. We have been working to identify its location, possible spread and efforts to control damage. Evidence of its existence is are "woolly" collections on the underside of hemlock branches along the stems where needles occur.
The browntail moth is already here. It is slowly spreading. Efforts to, not only identify its spread, but manage and minimize damage are in process. This moths' caterpillar has two distinct red/orange dots on its back. Its "tents" are also distinctive. They appear at the end of branches rather than closer to the trunk in crotches of the branches.
The browntail moth caterpillar has tiny (0.15 mm) poisonous hairs (setae) that cause dermatitis (skin rash) similar to poison ivy on sensitive individuals. Direct contact with the caterpillar or indirect contact with airborne hairs may cause the reaction. Most people affected by the hairs develop a localized rash lasting a few hours or several days but on some sensitive individuals the rash can be severe and can last for weeks.
Some of these bugs have not yet been reported in Maine. The emerald ash borer can devastate woodlots of ash trees. Once established, clear cutting and destroying the wood is often the best option. The small shiny green insects bore into the ash trees and destroy the tree from the inside. Sick ash trees should become suspect. The insects are tiny, and the actual holes in the tree's bark are also very small. The damage to the ash tree is the best way to begin identification.
What can a person do? Try and learn how to identify some of these nasty forest pests. The Maine Forest Service of the Maine Dept. of Ag., Conservation and Forestry has an excellent website for all invasives including these forest pests.
If you think you have identified one of these critters, do not be afraid to call the Maine Forest Service at
Remember, protecting the woods is one way to protect water quality. Do your part!
Conservation Too columns are written by staff at by the Kennebec County Soil and Water Conservation District in Augusta. For more information about the district and its projects, call Dale Finseth at