Invasive Species

Most baseball players use bats made from ash wood. It is strong, flexible, and lightweight, a perfect combination for sluggers.

But ash trees are under attack from a tiny insect. The emerald ash borer was first detected in Michigan in 2002. It is believed to have hitchhiked from its native Asia on wooden shipping materials. The iridescent green beetle lays eggs in the bark of ash trees, and when the eggs hatch, the larvae burrow into the tree. They cause damage that prevents the tree from taking up water and nutrient – so the tree usually dies within two years.

Ash borers are now in a number of states, including New York and Pennsylvania, and in Canada. It is believed that they spread within North America when people transported nursery plants or firewood from one place to another. It is now illegal to move ash firewood within or between some states and provinces.

Emerald ash borers have killed between 50 and 100 million ash trees in the North America. If they are not stopped, they could eliminate all the remaining ash trees on the continent.

Scientists are researching biological controls for the emerald ash borer. One approach is to use parasitic wasps; another approach is to use a fungus that contains an ingredient also used in some commercial pesticides. It is too early to know whether these efforts can save our ash trees. That’s why ash seed banks are also being developed.

As for baseball players, maple is also an option for wood bats, but with its shorter grain, it shatters more easily. So if you’re a baseball player or a baseball fan, you have good reason to be a treehugger.

Photo, taken on November 6, 2005, courtesy of Erik Jaeger via Flickr.