Homeowners do have options to protect trees
The evil green beetle is here.
Or almost here, and that's close enough.
Last week, two emerald ash borer infestations were discovered in Walworth County.
This week, workers will be hunting for the insect in Rock and Walworth counties.
Meanwhile, homeowners with ash trees are wondering if they can do anything to save their trees.
The short answer is yes.
For the last several years, researchers from Michigan State, Ohio State, Purdue University and UW-Madison have been tackling every angle of the pest problem from preventing its spread to keeping the pests in check with chemicals.
The beetles themselves only travel about a half mile on their own. They've been hitchhiking across country on firewood and other untreated lumber.
How bad is it? In the United States and Canada, the emerald ash borer has killed tens of millions of trees.
University researchers, the USDA Forest Service and the Wisconsin Department of Natural Recourses all agree: The emerald ash borer will spread, but how fast and how far is the question.
When might it arrive it Rock County?
"It's to the south of us, it's to the east of us, it's to the north of us and it's to the west of us," said Phyliss Williams of K&W Greenery, Janesville. "It's just a matter of time."
Williams has been recommending Merit, a Bayer product containing imidacloprid, to her customers who are concerned about their trees.
There are several professional formulations of insecticides containing imidacloprid.
They compete with a handful of other insecticides designed for use by arborists and other professionals, according to emeraldashborer.info/, a website run by the USDA Forest Service in conjunction with Michigan State, Purdue, and Ohio State University.
Homeowners, however, can buy and use Merit.
"It's insanely easy to do," Williams said.
The product is mixed with water and then poured around the base of the tree. The water is just the carrier for the chemical, which travels up the tree at a rate of one foot every two days, Williams said.
Professionals may apply the product in other ways, including soil or trunk injections.
Cost depends on the size of the tree.
The amount of chemical needed depends on the diameter of the tree.
Treating a large tree might cost between $50 and $75 a year, she said.
"It might save you that much on your air conditioning bill," Williams said.
Cutting down and removing a dead tree also is expensive.
Williams recommends preventive treatment.
The university specialists at emeraldashborer.info/ note that if the ash borer has not been detected within 10 to 15 miles of your location, your trees are at low risk. Scientists believe that in general, ash borers will spread between one-half mile to one mile each year.
However, once an area has been quarantined, the maps of the beetles' locations will not be updated.
And last week, a news release from the Wisconsin Department of Agriculture, Trade and Consumer Protection stated: "Walworth County will be quarantined soon. Neighboring counties may be added to the quarantine pending further review."
That means Rock and Jefferson counties.