Beneficial insect being released in Allamakee County to help manage the invasive Emerald Ash Borer
Mount Hosmer in Lansing is second location in Iowa to receive pests' natural enemy; harmless to humans
Beneficial insects are scheduled to be introduced at some point during this next week or so at Mount Hosmer City Park in Lansing for a biocontrol measure of the emerald ash borer (EAB). These very small stingless wasps target and kill EAB, a devastating exotic pest of ash trees. This control approach known as biological control reunites natural enemies with an invasive pest, in this case to help suppress EAB populations.
Following rigorous testing and research, one or more parasitic wasp species, native to Asia, have been released in 24 of the 27 states where EAB has been detected. Nearly two months ago this biocontrol effort in Iowa began in Fairfield in Jefferson County in southeast Iowa. Additional sites will be utilized pending resources and approval.
Like the county park outside Fairfield, two species of Asian parasitic wasps will be used to seek and destroy EAB at Mount Hosmer City Park in Lansing. Release locations are designed for site-approved public lands and parks and must meet specific guidelines.
Among those guidelines for location selection are the fact that the chosen area have an existing EAB population of "middle range," according to Mike Kintner, Iowa Department of Agriculture and Land Stewardship EAB and gypsy moth coordinator. "We want an area with an EAB population not too new that there aren't enough pests to combat, but not too heavily populated, either that we can't get the parasitoids established," Kintner said.
He also said the United States Department of Agriculture (USDA) prefers public land or park locations of 40 or more acres that have a certain ash tree threshold. "The Mount Hosmer location was also deemed an ideal location because of its proximity to heavily wooded areas, which will help facilitate the natural progression of the parasitoids," Kintner said.
The parasitoids are produced and supplied from the United States Department of Agriculture’s Animal and Plant Health Inspection Service (APHIS), Plant Protection and Quarantine (PPQ) EAB Parasitoid Rearing Facility in Brighton, MI. For parasitoid information, call 866-322-4512.
“Being able to utilize natural enemies is an approach we can use to our advantage to help reduce the spread of emerald ash borer,” said Kintner. "The predatory wasps will never offer complete control, but once established in an area they will spread naturally alongside with EAB, lessening the impact to ash trees across the landscape.”
The two species of parasitic wasps available from the USDA Animal and Plant Health Inspection Service target the larval and egg stages of EAB. Tetrastichus planipennisi female wasps, which are about the size of a grain of rice, lay eggs inside EAB larvae, terminating their development into adult beetles. Oobius agrili female wasps, which are the size of a gnat, lay eggs inside EAB eggs, parasitizing them before given the opportunity to hatch. Both species are described as being harmless to people and Kintner said the average person will not even notice their existence in the Mount Hosmer or other locations where they are being released.
More information about USDA’s Emerald Ash Borer Biocontrol Program can be found online at https://www.aphis.usda.gov/publications/plant_health/2014/faq_eab_biocon.... More information about EAB and other pests that are threatening Iowa’s tree population can be found at www.IowaTreePests.com.
