CAMDEN — In recent years, the state has been asking Maine residents to be on the lookout for an aphid-like invasive insect that is primarily found on the underside of hemlock twigs, at the bases of needles. But it was an astute tourist who recently discovered the hemlock woolly adelgid on two shade trees in Camden, and alerted the Maine Forest Service.

The insect, which came from Japan in the 1950s, causes premature needle drop and twig dieback, and can eventually lead to tree mortality, according to a Maine Department of Agriculture, Conservation and Forestry press release late Wednesday afternoon.

In Maine, the adelgid had previously been found this year in forested areas of Friendship and Owls Head, and the discovery of the insect in Camden begs the question whether it has also found its way into forests in and around town. If broader infestation is found in Camden, it will mark the third municipality in Knox Count, and the 43rd in the state, with a known established population in forest trees, according to the press release.

The hemlock woolly adelgid is a small, aphid-like insect, most often seen with white, waxy tendrils covering its body, making it resemble a miniature cotton ball. The adelgid is most often visible from late-October through July, and although there are adelgis on other conifers, the hemlock woolly adelgid is only found on hemlock trees, according to the press release.

A significant Maine tree species, hemlocks are often found near lakes and streams and contribute to Maine’s water quality. They also buffer stream temperatures, which can affect such species as brook trout. Also a favored landscape tree, hemlocks are important in deer wintering areas and contribute to the state’s forest economy, according to the press release.

“In some Maine communities with hemlock woolly adelgid, populations of the insect are scattered and hard to find,” according to the state Department of Agriculture. “In others, it can seem harder to find hemlocks free from adelgid than those with it. In the latter areas, pockets of noticeable adelgid-related decline are becoming apparent. For the first time this year, adelgid-related hemlock mortality has been noted during aerial survey.”

State officials, including the Maine Forest Service, is asking that people take some time to check their hemlocks for signs of the woolly adelgid, and if found, report it by calling 287-3147 or sending an email to forestinfo@maine.gov.

“Public participation in detecting and reporting this insect allows us to more wisely apply resources for management of the pest. Information on distribution helps Maine Forest Service target surveys and management activities, such as release of predator beetles,” said the press release.

For more information on the hemlock woolly adelgid, visit the Maine Forest Service website at this link.