Tree-killing emerald ash borer speading its reach in Missouri

Kansas City StarJuly 26, 2012 

— It’s finally reached Kansas City.

The Missouri Department of Agriculture officially confirmed Wednesday that the emerald ash borer, an insect native to Asia that feeds on and kills ash trees, has been found in Platte County.

Officials had been watching for its arrival ever since the emerald ash borer was found in southeast Missouri in 2008.

Wednesday’s announcement could be a slow-moving death sentence for many ash trees in the metro area.

“If there is just one borer, that tree will die,” said Mark Nelson, a forestry regional supervisor with the Missouri Department of Conservation. “It’s fatal 100 percent of the time.”

Ash trees are common in the metro area, with 40,000 lining Kansas City streets alone.

This new confirmation marks the farthest west the metallic green insect has ever been found. But it’s likely, Nelson said, that the borer has been in the area for some time.

“It’s hard to find the insect because the main damage is inside the tree,” he said. “It can go years undetected.”

As adults, the insects lay eggs on the bark of ash trees, which they feed off of. When the eggs hatch, larvae burrow into the layer of the tree that brings water and nutrients from the roots, and eat living tissue, eventually cutting off all nutrients.

The Platte County confirmation comes less than two weeks after a local arborist found signs of emerald ash borer damage in a tree south of Weatherby Lake.

Bret Cleveland, of Urban Tree Specialists, saw the signs when he responded to a dead-tree removal call in the Parkville area: the S-shaped larvae tunnels underneath peeling bark, the tiny D-shaped exit holes and the shoots sprouting out at the base of an otherwise dead tree — a sign the tree had fought to stay alive.

He took pictures and sent them immediately to the Missouri conservation department, which, along with other state departments, sent experts out to the site.

“We knew we needed to be on the lookout,” said Cleveland, who had been trained to look for signs of the insect. “But we didn’t expect to find it so soon.”

The emerald ash borer was first found in the United States in southeast Michigan in 2002 and was thought to have been transported here in cargo ships. It has since spread to more than 15 states, primarily through the transport of firewood.

It was discovered at a Wappapello Lake campground in Missouri’s Wayne County in 2008, and officials have said it was only a matter of time before the insect spread throughout the state.

The state also said Wednesday that ash borers had been found in Reynolds County, next to Wayne County in the southeast part of the state.

Nelson said those borers were found through traps.

Even with the Platte County confirmation, Nelson said it’s too soon to speculate on how fast an infestation could spread.

The Missouri Department of Agriculture, the Missouri Department of Conservation and members of the Animal and Plant Health Inspection Service will survey the area in half-mile increments until they’ve determined the perimeter of the infestation, Nelson said.

If it is substantial, the state agriculture department could enact a quarantine, regulating the movement of lumber, firewood, ash wood and the insect itself in and out of the state.

“That has been the strategy in the past and in other states,” Nelson said. But quarantines have proven only temporarily effective, as evident by the quick spread of the insect since 2002.

“Look at the number of states it’s gone through in 10 years,” said Dennis Patton, a horticulturist with Johnson County Extension.

Cleveland said recent droughts won’t help the problem because borers tend to seek out weakened or declining trees. Because the insects can only fly a half-mile, they are primarily spread through the transfer of lumber and firewood.

While there are prevention methods, insecticides that deter the insect are expensive, not 100 percent effective and often have to be applied by a professional, officials said.

Many communities have already chosen to beat the insects to the punch, chopping down ash trees and replacing them with different species before the bugs even arrived.

Kansas City removed about 60 ash trees from eight Benton Boulevard blocks in 2010. This past spring, St. Louis announced it would cut down more than 900 ash trees on the grounds surrounding the Gateway Arch.

Even if the infestation proves to be a substantial problem, the spread won’t happen overnight, and many urge those who own ash trees not to be alarmed.

“I have an ash tree in my front yard,” Patton said. “I’m not going to panic.”

He said if you own an ash tree, it doesn’t necessarily make sense to run out and treat it. Rather, it’s more important to spend money on water or properly pruning it, because the bugs tend to target unhealthy trees.

Nelson said if people think they’ve found specific signs of insect damage — a dying ash tree, S-shaped channels underneath loose bark and D-shaped exit holes — they should call a local forester.

“Just because you see a hole in a tree doesn’t mean it’s an emerald ash borer,” Nelson said.

Still, now that the emerald ash borer has been found in the Kansas City area, it means that in some time, probably a matter of years, the insect will spread.

Cleveland summed it up:

“It was a bad day for ash trees.”

McClatchy Washington Bureau is pleased to provide this opportunity to share information, experiences and observations about what's in the news. Some of the comments may be reprinted elsewhere in the site or in the newspaper. We encourage lively, open debate on the issues of the day, and ask that you refrain from profanity, hate speech, personal comments and remarks that are off point. Thank you for taking the time to offer your thoughts.

Commenting FAQs | Terms of Service