Local residents not yet acquainted with the emerald ash borer bug, know this – they’re already here.
The small, metallic, non-native beetle invaded the United States about 12 years ago and is on its way to eating the country’s ash tree population into extinction.
“Probably all of them are going to be gone within the next few years,” Minooka’s Public Works Superintendent Rob Tonarelli said of the village’s ash trees.
The ash borer is a small green beetle that lays its eggs between the crevices of tree bark.
When the eggs hatch, ash borer larvae burrow into the tree, eating their way to the tree’s inner bark and phloem. By doing this, the borers essentially cut off the tree’s circulation, making it impossible for it to transport water and nutrients throughout its branches.
According to Tonarelli, Minooka has about 750 ash trees growing in parkways and parks throughout the village, and that’s not including the numerous residential-owned trees.
Last year alone, Minooka public works removed about 100 ash trees because of EAB infestations. Tonarelli estimated the removal costs at about $30,000, but he anticipates spending another $60,000 in the coming year as the infestation seems to be spreading.
Finding and planting suitable replacement trees will only compound the mitigation costs.
“We’re likely going to exceed what we have budgeted this year for tree removal,” Tonarelli said.
As of 2013, the U.S. Department of Agriculture detected EAB epidemics in 20 states, including Illinois, leading the Agriculture Department of to brand the bug as “an extremely destructive beetle that poses an enormous threat to North America’s ash resources” in the most recent USDA report on the insect.
The first ash borer cases in Grundy County showed up about four years ago leading to Grundy’s inclusion in the state’s official “emerald ash borer quarantine zone.”
Becky Thomas, owner of Spring Grove Nursery in Mazon, said Grundy’s ash tree population won’t survive the EAB invasion.
“It is gloom and doom, really,” Thomas said. “They’re all going to die.”
The Illinois Department of Agriculture estimates about 20 percent of the Chicago area’s tree canopy is composed of ash trees.
Randy Timmons, a forester for the Illinois Department of Natural Resources Region 1, works out of Seneca and said the ash devastation is becoming more evident this year as the area is “peaking” in the EAB invasion cycle, which typically lasts a few years.
“It creates what they call ‘the wave’ where you have this high population peak,” Timmons said. “You really need to catch it before that peak in order to do any preventative work.”
Bouts of extreme weather have exasperated the problem, leading to more tree deaths this year.
The financial impact on local municipalities, and the state as a whole, could be tremendous if the area loses 20 percent of its canopy. Several cities, including Channahon, have enacted EAB action plans to mitigate the problem.
Thomas said there is a silver lining among the devastation.
“I think now, people will be more aware of tree diversity,” she said. “And they’ll realize how valuable those trees really are once they’re gone.”
Dealing with ash borers
• Buy local firewood to prevent spreading the infestation to other areas
• Check ash trees for small, ‘D’ shaped holes or burrows in the bark
• Have infested trees chemically treated or removed