And while it is no secret that human beings destroy their share of trees for a variety of different reasons, the emerald ash borer (Agrilus planipennis) has killed tens of millions of ash trees. The insect has the potential to kill most of the 8.7 billion ash trees in North America. Native to Asia, this beetle was accidentally imported into U.S ecosystems in Michigan in 2002. They have since spread throughout the eastern U.S. and southeastern Canada.
In order to control this pest, early warning of infestations is crucial. The survival of several species of ash tree is at stake. Censusing methods used in the past, however, have been expensive and difficult to implement. But scientists have learned a new way to battle the emerald ash borer by utilizing the services of a native ground wasp, Cerceris fumipennis. This wasp helps scientists estimate the abundance of EAB in a given area.
- fumipennis is a solitary hunting wasp. It preys on wood-boring buprestid beetles. The wasp will catch and paralyze a beetle with its stinger. It then carries it back to the nest, drags the beetle inside and lays an egg on it. When the egg hatches, the larva eats the beetle.
- fumipennis is valuable to scientist because when the wasps bring the beetles to their nests, surveyors can capture returning wasps with their prey to see whether the pest is in the area. Adult females may have several paralyzed beetles in her nest. Their nest is underground, but can be seen above ground as a pencil-sized hole with a pile of excavated soil around it.
Philip Careless at the University of Guelph, Ontario, Canada, started his biosurveillance program as a master’s degree project. Later, it was adopted in 2008 by U.S. forest health managers. Colleen Teerling, a forest entomologist with the Maine Department of Agriculture, Conservation and Forestry, was instrumental in setting up the C. fumipennis volunteer program. This programs is also known as WaspWatchers.