Ash trees in the W.K. Kellogg Forest are giving their lives in the battle to save Michigan forests from a ravenous bug.
The Kellogg trees, originally intended to help foresters determine genetic types best suited to Michigan, these days have a more urgent use: food and shelter for laboratory insects.
Scientists frantically are seeking a way to curb an invading Asian beetle, the emerald ash borer, before it wipes out every native ash tree in the state.
Tuesday, crews were at work in the Kellogg Forest plantation plots, selecting logs and branches from healthy trees to use in a range of laboratory and field experiments.
"They have to be fresh,'' said Therese Poland, research entomologist for the USDA Forest Service at Michigan State University in East Lansing, where lab experiments are being conducted with fresh cuttings.
"These beetles attack healthy living trees, not dead trees or downed materials.''
The experiments will study how the beetle spreads, what it eats, whether it will attack other trees when its preferred food source -- ash trees -- is gone, and what chemicals, applied in what manner, kill the insects, or at least slow them down.
Emerald ash borer was first found in the Detroit area four years ago; it probably came in years earlier with packing materials in a shipment from Asia. Finding lots of food here and no native enemies, the beetle population has exploded, moving quickly throughout southeastern Michigan and into Ohio and Indiana and leaving 15 million dead trees in its wake.
Infestations of the insect were found here earlier this month in Milham Park and at Loy Norrix High School.
Ash trees, prized for baseball bats, Native American baskets, lumber and in landscaping, have long been touted as the ideal tree to replace elms wiped out by Dutch elm disease and chestnuts killed by blight. Native ash trees grow in a range of conditions and climates and previously had almost no natural enemies.
But, Poland said, the heavy reliance on this ideal now illustrates the folly of ignoring diversity and counting too heavily on any single variety.
All bets are off when new diseases or insect pests hitch-hike from foreign lands -- with shipments or ballast water or tourists -- into areas where they've never been before. Not only are such invaders without natural enemies here, they are without manmade controls. Scientists haven't had a chance to adequately study their presence and figure out how to combat the damage they might cause.
Michigan scientists are on the front line in this battle, Poland said, "because it was dropped in our laps. A lot of people are depending on information we are generating.''
Studies include:
Capturing the essence of odors emitted by the trees to pin down what attracts the beetles, information that might be used to trap the insects or detect their presence earlier.
Looking at other tree species to see which might be hosts once the ash trees are all gone. So far, it appears the beetles can survive only on native ash trees, but "if they can host-shift, the whole cycle could start again, and that would be pretty much a catastrophe,'' said Deb McCullough, professor and forest entomologist at MSU.
Studying how populations spread by re-creating the Detroit outbreak, "like CSI with trees,'' McCullough said. "Only it takes longer -- trees can't tell you much.''
Dave Smitley, MSU Extension project leader for the emerald ash borer, said the first step is to secure funding for research. This year Congress allocated about $1 million for basic research, not just eradication or suppression efforts, an important distinction because "you have to know what you are (dealing with) before you can stop it,'' Smitley said.
He is working with McCullough to test aerial applications of insecticides in hopes of protecting not just individual trees on city streets or in back yards, but whole forests that are vulnerable to attack by the beetle, such as the stands in Augusta.
"I'm glad the Kellogg Forest is there, and those guys are incredibly helpful,'' McCullough said, but "we know we have just a couple of years'' before the forest may no longer be available as a source of healthy trees.
"Then our research may switch,'' she said. "We may be studying ash borer -- at Kellogg (Forest).''Kalamazoo Gazette
