Crews are drilling holes in just over 900 ash trees across Bay County. That’s because they’re creating an I-V port of sorts for the trees to ingest an insecticide that protects them against the invasive insect known as Emerald Ash Borer.
Emerald Ash Borer destroys the parts of an ash tree that allow it to soak nutrients up through the branches. If infested trees are left untreated, they will typically die in about 4-6 years.
Jeremy Lowell is the program coordinator for the Bay County Forest Sustainability Program. He said the organization has been working to protect around 3,000 publicly owned ash trees from EAB since 2003.
They do so by injecting the ash trees with an insecticide called Tree-age, which contains the active ingredient Emamectin Benzoate. The insecticide kills 99% of the EAB that feed on it, but the trees have tobe treated every three years to keep the EAB at bay.
“We do still have this lingering population of emerald ash borer that is around here,” Lowell said. “But with that being said, the pressure from the population on the trees is not as bad as it was when they first infested Michigan.”
Deb McCullough is a professor with Michigan State University’s who studies forest entomology. She’s an expert on Emerald Ash Borer, which has the ability to colonize all five of Michigan’s native ash species.
“The great majority of ash trees in Michigan have already been killed by Emerald Ash Borer if they were not being protected by a systemic insecticide,” McCullough said. “Just pulling a number out of my ear, probably 80% of the ash trees have been killed by EAB.”
Despite over two decades of extensive research and the rapid development of mitigation tactics, McCullough said EAB have not been contained, and likely never will be.
According to Lowell, the Bay County program recently conducted a study that affirms the need for continued treatment of ash trees. He said the study found the program is still regularly catching EAB throughout the county.
“We were able to do it quite regularly and at pretty good numbers compared to how hard they can be to catch,” he said. “The result of our project actually over exceeded our expectations for the amount we were going to catch.”
The full report from the study will be published in the fall.
Both Lowell and McCullough said ash trees are crucial to local ecology. The trees soak up excess storm water, provide habitats for wildlife, fend off invasive plant species and regulate oxygen levels in waterways.
Being proactive with treating ash trees for EAB also saves municipalities money, Lowell said. Preventing canopy deterioration and the need for tree removal helps to lower overall maintenance costs.
People can learn more about identifying infested ash trees and treatment methods through both state and national resources.
