3 Ways to Tell if Your Trees Are Being Damaged by Invasive Species

Maine's beautiful forests are susceptible to a host of invasive species. From wood borers to defoliators to disease, these species can quickly damage and kill a large amount of forest. Next time you take a walk through your woods, check for these signs of invasive species:

• Look at the bark. Insects like the Emerald Ash Borer and the Asian Longhorned Beetle bury their larvae beneath the bark of affected trees. Check for signs of tunneling or wounds in the bark pattern, D-shaped or round holes where the insects enter and exit, and piles of sawdust either falling from holes or at the base of the tree.

• Look at the foliage. Several species of insect consume foliage either as food or for nest building. Foliage that has Swiss cheese-like holes or bite patterns represents invasive caterpillar species like the Winter Moth. Species like the Browntailed Moth consume leaves as well, but in the winter they create nests using skeletonized leaves tied to the branches with silk, forming large clumps of larvae-filled web.

• Look at the needles. Insects like the Hemlock Woolly Adelgid and diseases like the Red Pine Scale that suck fluids from trees leave traces behind. Needles will often be covered with wool-like or wax-like deposits. Additionally, needles will be discolored or yellowing.

Other signs of disease, like large cankers or sores on the trunk or brown lesions on leaves, may represent fungal invasions and require further testing.

If you suspect a tree is infested with an invasive species, report your findings here.