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June 19, 2012 | 05:31 PMThe emerald ash borers are here.
Emerald ash borers are a part of that wave of invasive species that the state Department of Natural Resources seems to warn residents about every week, except this invader doesn't live in the lakes.
It lives exclusively in and on ash trees.
Last week marked the green little bark borer's arrival, with an infested tree found first near Walworth, and a second located by the city arborist in Lake Geneva.
"Now that it's discovered, we have a plan in place," said Dan Winkler Lake Geneva public works director.
The plan is to save select urban trees and to provide homeowners with the names of reputable arborists to help protect their trees, as well, Winkler said.
The city's public works committee has already recommended that steps be taken to save a proposed number of ash, Winkler said. The city's tree board is also expected to take up the issue this week.
Winkler said the tree board had a request for funding preventive treatment for the 2013 budget.
The emerald borer burned through the ash trees of Michigan, Indiana and Illinois and then started to creep into Wisconsin, entering Racine, Kenosha and Milwaukee counties. It's been slowly spreading from there.
Officials in Walworth County long knew that the pest was making its way here, Winkler said.
Mick Skwarok, plant pest and disease specialist with the state Department of Agriculture, Trade and Consumer Protection, said Walworth County will be quarantined within the next week or two.
He said a survey is now being done of neighboring Rock County, where the emerald ash borer has yet to be spotted.
For the majority of people, the quarantine means that hardwood firewood, regardless of tree species, cannot leave the quarantine area, Skwarok said.
Skwarok added that the quarantine does not apply to lumberyards or businesses that work in lumber. Processing lumber kills the ash borers and the finished lumber products must be inspected and certified according to state regulations.
Ash borer quarantines now exist in Brown, Crawford, Fond du Lac, Kenosha, La Crosse, Milwaukee, Ozaukee, Racine, Sheboygan, Vernon, Washington and Waukesha counties.
Information about the emerald ash borer may be found on the web at www.emeraldashborer.wi.gov.
According to Winkler, Lake Geneva has 300 ash trees in its parkways, which are the rights of ways and spaces between roads and sidewalks.
Of those, City Arborist John Foster is recommending that 200 be saved with a pre-emptive chemical treatment called "Treeage."
Winkler said experts suggest ash trees 28 inches in diameter or less are usually worth saving.
Treatment would cost about $10,000 total, Winkler said, with $3,000 for the application equipment and $7,000 for the chemical.
The chemical is said to kill the borer and protect the tree for two years after it's injected into the tree trunk, Winkler said.
The city's ash population is relatively small compared to its inventory of between 4,000 and 5,000 trees on its parkways, Winkler said. He said the majority of the city's trees, between 50 and 60 percent, are maples.
The city faced two choices. Do nothing and then remove the trees as they are infected.
Or, select the best trees to be saved and treat them until the infestation has run its course.
The choice was an easy one, Winkler said.
"We are tree city," he said. "It behooves us to preserve the trees we have."
What's more, the cost of removing diseased trees is about the same as treating them. Except the city has a chance to keep the trees that are treated.
Winkler said Foster is recommending that the city get everything in place for the fall.
The emerald ash borer feeds on the inside of the tree, eating away at the spongy layer of tissue just beneath the bark.
This feeding destroys that tissue and stops the trees' ability to move water and nutrients from the roots to the rest of the tree. The tree starves and eventually dies.
The treatment uses that spongy tissue to travel from trunk to branches. It takes several weeks for the chemical to reach to the outer and upper branches, so applying it to trees already dying from the infestation doesn't work, Winkler said.
Winkler said the infested tree in Lake Geneva was on North Street across from Talmer Bank. That tree was taken down Friday morning and the branches were chipped, as recommended by the DNR, he said.
Once the chips dry out, the bugs are dead, he said.
Any parts of the tree too big to chip will be taken to an approved disposal area.
While there is no public program to help private property owners protect their ash trees, Winkler said the city will develop a list of qualified arborists for local residents who want their ash trees treated to prevent infestation, or to remove trees too far gone to save.
"We don't want people to get ripped off," Winkler said.