Little can be done to stop the emerald ash borer’s march across Nebraska. But the USDA has introduced a weapon it hopes will someday slow the infestation that’s killing the popular ash tree: three tiny wasps with intimidating names. The tetrastichus planipennisi, the spathius galinae and the oobius agrili feast on the emerald ash borer in its home range in eastern Asia.
After extensive testing by the USDA, some were brought to the United States 10 years ago to help control the emerald ash borer, mainly in the east and around the Great Lakes. Some were released in Nebraska last summer, and will be again when the insect emerges in May and June.
“The hope in getting these established is it might help future generations of ash trees after the initial wave of EAB has gone through,’’ said David Olson, a forest health specialist with the Nebraska Forest Service. “If this is in place, it could suppress EAB to a level where it won’t kill the tree. It might help to keep the EAB population lower.’’
The wasps have been released in wooded sites where EAB is flourishing in Nebraska: Lincoln, Fremont, Mahoney State Park and Platte River State Park. The beetle has been found in Omaha, Lincoln, Fremont, Ashland and Greenwood, starting in 2016.
People don’t need to worry about being stung by the wasps, Olson said. “Most of them are very, very small, a couple of millimeters in length,’’ he said. “Although they have something that looks like a stinger, they are stingerless.’’
The wasps are grown at a containment facility in Michigan, and then shared with Nebraska as amounts allow. The oobius agrili lays its own eggs inside the EAB eggs, and the larva eats its way out after hatching. The other wasps lay their eggs in the larvae of the EAB. Emerald ash borer is the only thing they eat, so they won’t go after other species, Olson said.
Ash trees were planted extensively across the United States because they did well as a street tree. But there is no documented resistance to EAB, which arrived on a wood pallet or packing material in the Detroit area in the 1990s. Most states east of Nebraska are infested, and EAB has moved as far west as the Boulder area of Colorado. It has no natural enemies here, so it has spread unchecked.
“It’s kind of the golden scenario for the beetle,’’ Olson said. It will take a few years to determine if the wasps have become established and will make an impact. “It could slow down EAB a little bit,’’ Olson said. “The real focus is just for the future.’’
https://www.omaha.com/inspiredlivin...cle_709efe34-45d1-5398-bcfd-4593ec2ae157.html
After extensive testing by the USDA, some were brought to the United States 10 years ago to help control the emerald ash borer, mainly in the east and around the Great Lakes. Some were released in Nebraska last summer, and will be again when the insect emerges in May and June.
“The hope in getting these established is it might help future generations of ash trees after the initial wave of EAB has gone through,’’ said David Olson, a forest health specialist with the Nebraska Forest Service. “If this is in place, it could suppress EAB to a level where it won’t kill the tree. It might help to keep the EAB population lower.’’
The wasps have been released in wooded sites where EAB is flourishing in Nebraska: Lincoln, Fremont, Mahoney State Park and Platte River State Park. The beetle has been found in Omaha, Lincoln, Fremont, Ashland and Greenwood, starting in 2016.
People don’t need to worry about being stung by the wasps, Olson said. “Most of them are very, very small, a couple of millimeters in length,’’ he said. “Although they have something that looks like a stinger, they are stingerless.’’
The wasps are grown at a containment facility in Michigan, and then shared with Nebraska as amounts allow. The oobius agrili lays its own eggs inside the EAB eggs, and the larva eats its way out after hatching. The other wasps lay their eggs in the larvae of the EAB. Emerald ash borer is the only thing they eat, so they won’t go after other species, Olson said.
Ash trees were planted extensively across the United States because they did well as a street tree. But there is no documented resistance to EAB, which arrived on a wood pallet or packing material in the Detroit area in the 1990s. Most states east of Nebraska are infested, and EAB has moved as far west as the Boulder area of Colorado. It has no natural enemies here, so it has spread unchecked.
“It’s kind of the golden scenario for the beetle,’’ Olson said. It will take a few years to determine if the wasps have become established and will make an impact. “It could slow down EAB a little bit,’’ Olson said. “The real focus is just for the future.’’
https://www.omaha.com/inspiredlivin...cle_709efe34-45d1-5398-bcfd-4593ec2ae157.html
