Willowbrook Park

NYC PARKS RELEASES PARASITOID WASPS FOR THE FIRST TIME EVER TO COMBAT THE EMERALD ASH BORER

NYC Parks today partnered with the New York State Department of Environmental Conservation (NYSDEC) to release parasitoid wasps in Willowbrook Park. The wasps are a form of biological control for Emerald Ash Borer (EAB) beetles which are threatening New York City’s ash trees. The second of two releases, this marks the first time that New York City has introduced parasitoid wasps into the city to combat the spread of the EAB.

The parasitoid wasps will serve to reduce the EAB’s reproductive ability and control the population size over time. Originating from the EAB’s natural habitat, north-east Asia, the release of the parasitoid wasps are a form of biological control. This is the practice of releasing natural enemies from a pest’s native region, with the goal of controlling the population of the pest.

The parasitoid wasp release was made possible by a $75,000 grant from the NYCDEC’s Urban Community Forestry Program.

The EAB is an invasive Asian beetle that infests and kills North American ash tree species. The larval stage of EAB feeds under the bark of ash trees, cutting off the flow of water and nutrients, causing the tree to die within 2-4 years. EAB has no known natural enemies in North America. First found in North America in 2002, EAB has killed tens of millions of trees in the United States and Canada.