Pest sets in at St. Francois State Park: Emerald ash borer

A popular local state park is under attack from an Asian pest with a pretty name: the emerald ash borer.

The borer, which likely hitched a ride in the early 2000s on wooden packing material via shipping agents from Asia, decimates ash trees from birth. In the larval stage, the insects feed on the inner bark of the tree, causing the most damage since it prevents nutrients from being absorbed. Later, as bright-green, emerald-colored adults, they nibble on the tree’s foliage.

Hundreds of millions of trees in 34 states have been wiped out since the exotic beetle was first reported near Detroit, Michigan, in 2002. According to the Missouri Department of Agriculture, it was discovered in southeast Missouri in July 2008 in Wayne County and, by September 2013, Missouri’s quarantine expanded to include all 114 counties and the City of St. Louis.

“Like many other parks across Missouri, St. Francois has been hit by the Emerald Ash Borer,” read a post written by Naturalist Mary Crowell on St. Francois State Park’s Facebook page. “This little pest is killing our ash trees. Park staff is removing these dead and dying trees from our campground this winter.”

Crowell emphasized the trees being cut are in the day-use area, to prevent hazards from falling limbs.

Several of the park’s fans had noticed trees had been cut or were declining, and a couple posters wondered whether efforts would be made to replant what has been lost and cut down.

“Right now we are just in the phase of removing all the hazardous trees,” was Crowell’s answer. “Once that is completed we will evaluate the next step.”

It’s been surmised that the biggest culprit for the emerald ash borer’s spread is the transport of firewood among homes and campgrounds. It’s why many campgrounds urge visitors to use firewood found on-site and purchased from park concessions, instead of bringing in wood from other places that might be arborially infected by the beetle.

“If you’ll notice, driving up and down Highway 67, if you see what they call ‘blonding,’ or places where woodpeckers have stripped away a tree’s bark, you can bet it’s been infected by emerald ash borer,” Crowell said. She agreed that, once one knows what to look for in terms of blonding, it’s difficult not to notice it everywhere.

“I believe they first found it in Missouri in Wappapello State Park, down in Wayne County,” Crowell said. “To my knowledge, the borers have spread throughout all parks in Missouri.” She noted the Gateway Arch in St. Louis chopped down about 800 ash trees on the grounds as part of their renovation project, but also in anticipation of the eventual infestation of emerald ash borer.

An adult emerald ash borer found in a tree at St. Francois State Park.

Sarah Haas is the assistant editor for the Daily Journal. She can be reached at 573-518-3617 or at shaas@dailyjournalonline.com.