Coming to a Forest Near You: Emerald Ash Borer was originally published in the BFEC Newsletter, Vol. 18/No. 1, Winter 2014.
While “emerald” may give the illusion of beauty, beware of this boring beetle, which is on track to do unprecedented damage to Ohio’s four billion ash trees. The emerald ash borer (EAB) is originally from Asia and was first sighted in 2002 in southeast Michigan, likely having hitched a ride on pallet wood or other ash products. It is now found in 16 states in the Great Lakes and Mid-Atlantic regions.
Ash trees have very little resistance to the EAB, which damages the tree in larval form. Grubs tunnel just under the bark, where they chew the outer layer of wood that comprises the tree’s circulatory system. Left unable to send sugars down to roots and water and nutrients up to leaves, trees usually succumb to the damage within five years.
The EAB was first found in Knox County near Centerburg in 2012. The infestation usually advances at a rate of about two miles per year, though this can be hastened when infected firewood introduces the bug to new places. Though the ODNR initially attempted to quarantine the bug by banning the movement of firewood, the ban has been lifted now that the bug is in all but 16 of Ohio’s 88 counties.
Maybe. Treating trees with insecticide (via soaking roots with the chemical or spraying foliage) has had mixed results. A key to success is starting treatment before the tree becomes sick, since it needs a healthy circulatory system to spread the insecticide throughout all of its tissues. Visit agri.ohio.gov/eab to learn about treatment options.
The bugs’ presence is told by the “D” shaped hole they leave in bark when adults above (pictured). Adult beetles may also be seen flying May through September.