EAB Spread Causes Further Quarantines in Illinois

The Illinois Department of Agriculture has expanded its emerald ash borer quarantine area to include all or part of three central Illinois counties, restricting the movement of cut firewood and some landscaping materials.

The ag department added Woodford and McLean counties and the eastern flank of Marshall County to its list of areas either because the invasive insect has been trapped in the counties or in close proximity. A total of 21 counties now are fully or partly quarantined.

Logan County has not yet been directly affected, although the quarantine area now sits flush with its northeastern border.

And it’s possible the ash borer is already here.

It typically takes several years for signs of an infestation to show, said John Fulton, Unit Leader of the Logan County University of Illinois Extension Service.

Once the ash borer has invaded an area, the only way to get rid of it is to cut down all the trees that it has infested. Fulton said Logan County has a lot — perhaps thousands — of ash trees.

In the past, Logan County had a run-in with Dutch Elm Disease, which eventually wiped out the population of the species. Unfortunately, many of those dead elms were replaced with ash trees.

On the upside, the emerald ash borer does not spread quickly on its own. Generally, infestations occur as a result of people transporting firewood or lumber to new areas.

The expansion of the quarantine zone is the result of an emerald ash borer survey that began in the spring with the placement of 4,689 sticky, purple traps across central, northwestern and southern Illinois. Seven of the traps contained the insects: one each in Bureau and Lake counties, three in LaSalle County and two in McLean County.

“Woodford and Marshall (counties) are between McLean (County) and the prior southern-most point of the quarantine boundary,” ag department spokesman Jeff Squibb said Thursday, explaining the inclusion of those counties in the quarantine.

The adult insects feed on ash foliage, but insect larvae feed on the inner bark, disrupting the tree’s ability to transport water and nutrients - killing the tree over a span of three to five years.

The quarantine prohibits the movement outside the affected counties of ash trees of any size, ash limbs and branches, bark from ash trees, ash tree wood chips larger than one inch in size and ash logs and lumber with the bark or outer inch of sapwood still attached.

The quarantine additionally forbids transport outside the affected counties county of any cut, non-coniferous firewood because officials often can’t determine whether the wood came from an ash tree. The invasive insect likely entered the state in tainted firewood, Squibb said.

“Any cut firewood is subject to the quarantine,” he said.

Anyone caught violating the quarantine without permission from the state is subject to a $500 fine, and Squibb said the department would be in contact with area nurseries and contractors who transport large quantities of wood to work on compliance agreements.

“It does to a large extent depend on voluntary compliance,” he said.