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Beetle mania

The emerald ash borer beetle has killed more than 70 million ash trees in North America. And the insects show no signs of slowing down soon. The emerald ash borer has entered New York, too, and threatens the 900 million ash trees in the state, which amount to seven percent of the state’s tree population. Early efforts have failed to stop the spread. But Melissa Fierke, an assistant professor at the State University of New York College of Environmental Science and Forestry, aims to try. Fierke and her team of graduate students are conducting research to try to slow down the destruction, track its spread, and most importantly, document the ash trees still present. ‘Our lab is mostly about documentation of what we have,’ Fierke said. ‘This provides baseline information that can be used in future restoration efforts.’ Fierke began her work on the beetle in 2007, writing grants and recruiting students to help with her research. Fierke, along with her students Peter Rockermann and Warren Hellman, conducts her research all over New York and in Illick Hall at ESF. The emerald ash borer is about half an inch in length and feeds solely on ash trees, first as larvae that feed on the inner bark, then as adults consuming the foliage. The larvae consume a tree’s vital tissues that store water and nutrients. As a result, most ash trees die within two years of infestation. The beetle currently has no predators to keep its population in check. The emerald ash borer was first discovered in the United States in southeast Michigan in 2002. Since 2002, it has spread to 12 states and parts of Canada. The beetle’s first appearance occurred in Randolph, N.Y. in June 2009. Rockermann, a graduate environmental and forest biology student, concentrates on documenting different types of moths that rely on the ash trees. He aims to preserve their population before the ash tree is eradicated completely and evaluate the ecological damage the beetle has done. Hellman, a graduate forest entomology student, is using a native digger wasp to track the spread of the emerald ash borer beetle in New York. The wasp feeds on metallic wood-boring beetles and will control the destructive beetle’s population. Along with the wasps, traps were hung across the state early in the season to identify if the emerald ash borer has spread. The traps will not be checked until late summer and more will be known once that happens, Hellman said. The spread of the beetles has been so rapid that Asian parasitoids were also introduced to combat the species. A parasitoid is an organism that lives on an animal, in this case the beetle, and eventually kills the host by feasting on it. ‘With the terrible potential of the emerald ash borer in mind, Asian parasatoids have been identified and released. However, we don’t know how they will affect our native compliment of metallic wood-boring beetles.’ Fierke said. Despite the efforts, Fierke said there has been little success in stopping the destruction. The outbreak is estimated to have started 15 years before scientists identified it. Fierke said the future of the ash tree looks bleak. She predicts that naturally occurring ash trees in the United States will be gone within 100 to 200 years. Ash seeds don’t survive for long with the infestation, making preservation difficult, she said. The only way to keep a seed source is to grow trees in unaffected or protected areas. People play a crucial role in the spread of the emerald ash borer beetles, with the majority of infestations coming from spreading already infested wood, such as firewood and ash products. To combat the problem, many states have implemented quarantines – including one around the site in Randolph – banning the transportation of ash wood without permission from state agencies. These quarantines are being enforced with hefty fines for offenders. In addition to tracking the emerald ash borer beetles, Fierke is also working to combat an invasive wood wasp. She’s not planning on giving up on either fight anytime soon. ‘I expect that work on these two particular invasive species will be ongoing throughout my career,’ she said. jlsiart@syr.edu





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