Ash logs undergoing vacuum treatment to kill emerald ash borer larvae. (U.S. Forest Service)
The shiny green one-half-inch-long, one-eighth-inch-wide emerald ash borer has destroyed tens of millions of ash trees in the U.S. since the beetle’s discovery in 2002 in Detroit.
The real Ash trees comprise around seven percent of the trees in eastern U.S. forests. In urban areas, ash trees make up about 50 percent of street trees.
Ash trees are important both economically and ecologically. A wide array of products are made from ash wood, including baseball bats, tool handles, pool cues, furniture, cabinets, oars, and acoustic and electric guitars. Ash seeds are an important food source for birds, mice, squirrels, and other small mammals. Ash trees also provide essential habitat for cavity nesting birds, such as woodpeckers, owls, and wood ducks. Read more »
Photo of S. galinae by Jian Duan, Research Entomologist, USDA ARS Beneficial Insects Introduction Research Unit
May 18-24, 2014 is Emerald Ash Borer Awareness Week
In our efforts to preserve and protect American ash trees from the damaging and invasive emerald ash borer (EAB) beetle, APHIS is working diligently to find and implement solutions that have the potential to successfully conserve this beautiful natural resource. Spathius galinae (S. galinae) just could be that newest weapon in the arsenal.
The tiny stingless wasp, about the size of a typical mosquito, targets and attacks EAB larvae living under the bark of ash trees. Crawling along the bark ridges and furrows, S. galinae somehow senses EAB larvae hidden below. The wasp not only accurately locates its target, but also is able to determine relative size—showing preference for large EAB larvae. Once a suitable larva is detected, the female wasp uses its long egg-laying organ (ovipositor) like a hydraulic drill to bore down through the layers of bark and deposit between 5 and 15 eggs on its host. After the eggs hatch, the wasp offspring feed on the EAB larva, eventually killing it. A new generation of S. galinae emerges in about 35 days. Read more »