There are things that can be done to try and combat their movements. Special insecticides can be put into the vessels of the trees, but not until the weather warms up. During the winter months the vessels inside the threes are close to frozen, and the insecticide wouldn’t be able to flow fluidly through the trees. Mostly, Rathje said, people need to just constantly check their ash trees for signs of EAB.
According to the Iowa DNR, signs for the presence of EAB in ash trees include thinning or dying branches in the top of the trees, water sprouts halfway up the trunk, feeding notches, woodpecker feeding sites, S-shape feeding paths under dead bark and 1/8 inch D-shaped exit holes in the bark.
Anyone who finds possible EAB infestations in ash trees should contact the Iowa DNR right away.
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