7-20-17 Emerald Ash Borer

The Emerald Ash Borer, shown here, has been spotted in Andrew County this year. After being seen in Buchanan County in 2015 and DeKalb County in 2016, Andrew County is the third county in northwestern Missouri to have evidence of the Emerald Ash Borer.

It seems like, each summer, the Emerald Ash Borer makes its way to a place it’s never been seen before.

The Missouri Department of Conservation recently has confirmed the presence of the Emerald Ash Borer in Andrew County. Described as a “green beetle that only attacks ash trees,” resource forester Jason Severe said the damage happens when the beetles are in their larval stages.

“The larvae hatch inside the tree and feed beneath the bark, on the tissue that carries water and nutrients throughout the tree,” Severe said. “It basically girdles the tree and makes it impossible to conduct water and nutrients that help the tree live.

“It doesn’t really affect the structure as much, but trees that are more heavily infected will have their branches die back. The structure of the tree doesn’t get hurt too much.”

The insect species is native to Asia, but first showed up in America in the early 2000s when pallet material being transported to the United States was infected with it. The first known cases of damage from the Emerald Ash Borer were in Michigan.

By 2011, the tree disease had made it to the Kansas City area, according to Severe, and it spread from there.

“Since 2011, the Emerald Ash Borer has been found in 38 counties and the City of St. Louis,” Severe said. “The insect was spotted in Buchanan County in 2015 and DeKalb in 2016.

“Back in June, we found it in Savannah, and over in the St. Joseph area there are infected trees showing a lot more severe symptoms of being affected by the Emerald Ash Borer. The drought conditions we’ve experienced this summer have made it worse, increasing the stress on those trees from what they’ve already experienced being affected by the insect.”

Ash trees became common in the state of Missouri back in the 1970s, according to Severe, when the Dutch Elm disease came to America and affected the population of the American Elm tree. Severe said ash trees were commonly planted to replace elm trees because ash trees grow at a rapid rate.

“The main impact is the number of ash trees that have been planted in cities,” Severe noted. “If insects get into the cities and affect those trees, it could cause those areas to be devoid for a number of years until new trees can be established.”

The main way that the Emerald Ash Borer is passed from one place to another is by transporting firewood. Severe said that would be a good way to prevent the spread of the insect.

“The best thing to do would be to avoid bringing trees from areas where we’ve spotted the insect to areas where the insect hasn’t been spotted yet,” Severe said. “We recommend people only use local firewood that was grown within 10 miles of where it’s being burned.

“There are some insecticides that have been shown to be effective against the Emerald Ash Borer, but we typically don’t recommend that people use the insecticide unless it’s known to be in the area already. The treatments can be costly, and they have to be repeated at least every couple of years or so.”

Since the Emerald Ash Borer has yet to be seen in Nodaway County, Severe said he wouldn’t recommend that people seek out the insecticide treatments until it’s known to have entered the county. 

Tom Pinney is a staff writer for the Maryville Daily Forum. You can reach him at tpinney@maryvilledailyforum.com or by calling the newspaper at 660.562.2424.