The adventurous journey of the emerald ash borer (EAB, part two)

This is the emerald ash borer. 

The emerald ash borer's home is in eastern Asia. It is native to northern China, Korea, eastern Russia, and Japan. In its natural habitat, the emerald ash borer is not a threat. Asian ash trees are resistant to the insect. In addition, because, in eastern Asia, there are numerous predators around to keep the emerald ash borer population in check. According to the U.S. Forest Service, "Asian ash trees have evolved resistance genes and mechanisms that allow them to coexist with the emerald ash borer." One long-term goal of the U.S. Forest Service is to develop an emerald ash borer-resistant hybrid ash species. Mark Whitmore, an entomologist from Cornell University, emphasized the importance of conserving the ash genome. "We have to save trees and we must collect the seeds from the best-looking plants. The surviving trees are worth gold." These are the seeds that could be used to create the hybrid ash species of the future.

So, how did the emerald ash borer get here, to Grand Island, New York, all the way from China?

It seems that the insects were stow aways in wooden pallets that were used to stabilize shipments from China to the U.S. automobile industry in Michigan. It is possible that the first emerald ash borers came to Michigan in the late 1980s. By 2002, people started noticing that the ash trees in Michigan were stressed and were dying. "A forest pathologist near Detroit took a sample of a bug from a dying tree. No one could identify the insect," Mark explained. 

By the time that the insect was identified as the emerald ash borer, it was already too late for many of Michigan's ash trees. Between 2005 and 2007,Michigan's cities experienced a catastrophe. The loss of ash trees was close to one hundred percent in urban areas, such as Detroit. The city's response was to plant a diversity of trees to replace the ash trees. These include lindens and various types of oaks and other trees. If there is a future disaster that wipes out a single species of tree, it will not devastate the entire city.

The emerald ash borer is always on the move. According to Mark, an emerald ash borer, which is a small insect, can fly up to 20 miles in a single day. But it doesn't travel from place to place only by flying. Emerald ash borers are transported on fire wood, which is why the New York State Department of Environmental Conservation put rules into place about not moving firewood more than 50 miles. The emerald ash borer also travels by car. "They like to glom onto vehicles," Mark said.  He told the story of a man who drove eighty miles per hour on the Thruway. "After twenty miles, the emerald ash borer was still on the man's windshield." 

The emerald ash borer continues to travel, leaving devastation in its wake. 

Next time: The costs of the emerald ash borer and ways to protect a community under threat from an infestation.