(Iowa) — Emerald ash borer, an invasive insect known for killing Ash trees, has now been detected in every Iowa county except for one.
The United States Department of Agriculture says the latest detection is in Palo Alto county in northwest Iowa. Emmet County, on the far northern Iowa border, is the only remaining county free of the pest. Anyone who suspects Emerald ash borer in Emmett County is strongly urged to report it to the DNR.
The insect can kill an Ash tree in within two years.
Landowners with ash trees on their property should begin to consider a course of action for at risk trees, which are generally those within a 15-mile radius of a known infestation. Landowners and managers can wait and see what happens, remove declining ash trees and replace them with other species, or use preventive insecticide treatments to preserve and protect valuable and healthy ash trees. The best time to treat for EAB is in the spring, from mid-April to mid-May. Insecticides are most effective when the ash tree is actively growing, and uptake is at its peak. Tree service companies can apply insecticide trunk injections through the summer if soil moisture is available.