ash trees

Emerald ash borer (EAB) beetle is an invasive wood boring beetle, first detected in July 2002 in southeastern Michigan. The pest attacks and kills ash trees and it is responsible for the death and decline of tens of millions of ash in 25 states. EAB lives under the bark and when people move EAB-infested firewood they unknowingly move the pest. During EAB Awareness Week (May 22-28) leave HungryPests behind and don’t move firewood.

Do you remember the eighties television show MacGyver? Science genius turns secret agent. Each week Angus MacGyver—armed with only a pen, aerosol spray can and a Swiss Army knife—successfully disarms the bomb and saves the day! The following week, it’s a shoe horn, jumper cables and a screwdriver…then a thermos, belt buckle….you get the drift. Sixty minutes of ingenious, nail-biting problem-solving.

Although the show’s final episode aired almost 25 years ago, the spirit of Angus lives on at the USDA’s Emerald Ash Borer (EAB) biological control production facility, where USDA is strategically rearing natural enemies to combat this destructive pest.  Mass rearing biocontrol agents (stingless wasps) is a delicate process that’s time-sensitive, labor-intensive, and laden with problem-solving opportunities.

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.

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.