Invasion from Asia to Michigan to New York

The emerald ash borer threatens the existence of ash trees

Story by Kyler Klix

Imagine millions of trees disappearing from the North Country. Trees in the forest, the city, and even your own backyard are prone to decaying from the inside out, leaving them rotting on the sides of roads and inside forests. This is a danger the North Country faces after the discovery of an invasive species known as the emerald ash borer was found in June 2009 in New York, and some parts of Canada.

The emerald ash borer hitched a ride from Asia to the United States. They feed primarily on ash trees. New York is home to green, white, and black ash trees. It is unknown how the bug was transported, but since it was discovered in 2002 in Michigan, more than 40 million ash trees have died or are in the process.

“If we can slow it down, maybe something will come along in the next few years.”

Ash trees are important for a number of reasons. Most of them were planted during the 1930s to make up for the elm trees that were disappearing from Dutch elm disease. The trees also provide habitats and food sources for birds and mammals. The disappearance of ash trees could lead to temperature changes (from the shade), increased air pollution, and the impact of having dead trees everywhere that would need to be removed. Ash trees already affected by the bugs will show “S”-shaped carvings on the inside of the bark on trees. The trees will also wilt, branches will die, and the leaves of the tree will not be as bushy.

A major problem that could arise is rotting ash trees in towns and cities. Rob Cole, a forest health field supervisor for the DEC, says this could lead to property damage, or a person getting injured. It will also cost towns and cities lots of money and resources to take care of all the dead trees and debris.
“We’re more concerned about towns or cities with hundreds or thousands of ash trees,” Cole said.

Kennoth Carnes, from the New York State Department of Agriculture and Markets says it was not landscape trees planted by the New York State Department of Transportation, or from furniture shipped to Canada. “The landscape trees were planted in 2004, but did not show any signs of EAB damage until 2007,” he explains. This means that the bugs were already in the area before the trees were planted.

It is unknown how the bugs traveled to North America. The most likely scenario is that they were introduced in ash wood used for shipping pallets, wooden packing materials, or shipping containers. The bugs also do not spread very fast because they do not travel far. A typical EAB travels less than a half-mile away from the tree they were developed in, and the natural spread of the bug travels one mile every season. This means the bug was transported from Michigan to New York because of the distance. The bugs have invaded 13 states, and the Canadian provinces of Ontario and Quebec, which is a major concern of the multiple states and provinces.

“I believe that campers from Michigan or Ohio transporting firewood or interstate movement of ash logs could have introduced EAB to Randolph, N.Y.,” Carnes says. Since this is a common idea, there have been several bans on transporting firewood for a distance past the original spot.

Because of the beetles’ characteristics, it must survive for a few years before its existence is well-known. This means that since it was discovered in Michigan in 2002, it actually had been there for several years before. Many moves have been made to prevent the spreading of the species to other parts of the state and the country. Both Federal and State governments have made moves to quarantine certain counties that the EAB are in. A law in the summer of 2009 made it illegal to transfer firewood or other logging products from one county to another.

This artificial spread is what environmentalists are worried about the most. If the bug is being transported long distances, the impact could be more devastating.

“If we can slow down the artificial spread, it will help people adapt their businesses and use a different type of wood,” Cole says. Cole also explained that by keeping the spread natural, it will give researchers more time to find a solution to the EAB. By spreading the impact out over a longer period of time, the municipalities will spend a few thousand dollars a year instead of spending a much larger amount in one year. “If we can slow it down, maybe something will come along in the next few years,” he hopes.

To track the spread of the EAB, the DEC placed purple traps across areas close to infestation in a grid pattern. Professor of Environmental Science Kenneth Adams helped set some of the traps over the past two summers. He says the trap is made of an oil attractant and the sticky outer service attracts bugs of all types. There was no detection of EAB in northern New York. The major threat to the North Country would come from Canada and western New York, where the EAB was discovered in Randolph.

“If we don’t know they are here, then the impact could be much worse.”

“The strategies used by agencies that are involved with being concerned about non-native species have chosen to be preemptive,” Adams says. He says the most important thing to do is to raise awareness about the problem, and all the agencies involved have placed posters and passed out other information to keep the public notified. “The alternative is much worse,” he says. “If we don’t know they are here, then the impact could be much worse.”

It is very difficult to get rid of an invasive insect. Given how widespread these insects are, it might be impossible. The EAB lives commonly for about three weeks while they are invading, but once they have established themselves, a typical adult EAB will live for about a year.

Cole said there has been a seed-collecting process through various organizations to ensure that ash trees will not become extinct. The seeds would be used to replant if the EAB is eradicated, or if ash can be genetically modified to be resistant to EAB.

How concerned are you about the emerald ash borer?