Minnesota adding a sticky new tool in the fight against emerald ash borer

Posted: May 30, 2012

ST. PAUL, Minn – The Minnesota Department of Agriculture (MDA) is rolling out a new monitoring technique in the hunt for emerald ash borer (EAB). The new approach is designed to lure any male EAB beetles in the area into a sticky trap as they search for a mate.

In the summer, male EAB beetles cruise around ash trees searching for female beetles. When they spot a potential mate on an ash tree leaf, they land nearby to investigate. MDA will seek to exploit this behavior pattern by setting traps that consist of dead female beetle decoys covered with sticky spray. As the male beetles arrive to visit the females, they will get stuck. When field staff go back to remove the decoy later in the season, the presence of a “stuck” male beetle will help indicate a local infestation.
The new approach is called STUC (Sticky Traps Using Cadavers), and it will be conducted during EAB’s peak flight season starting this week. A total of 125 ash trees have been selected in Minneapolis and St. Paul. Five female decoy beetles are placed on different areas of the tree and covered with Tanglefoot®, a sticky substance.
STUC is modeled on field research by Penn State University conducted in Michigan. This will be the first implementation test of this approach, and is a collaborative project with the University of Minnesota, USDA, and cities of Falcon Heights, Lauderdale, Minneapolis, and St. Paul. The approach will be tried on a limited basis this year, and results of this study will help determine whether the method is employed on a larger scale as a complement to the purple cardboard traps now used to monitor for EAB.
“Purple triangle traps are best used to find new infestations,” said Geir Friisoe, MDA’s Plant Protection Division Director. “In areas already known to have EAB, we are testing new detection methods to help us define the leading edges of these infestations in the Twin Cities.”
STUC is one of several EAB studies funded by a grant from the Minnesota Environment and Natural Resources Trust Fund as recommended by Legislative-Citizen Commission on Minnesota Resources (LCCMR). EAB is one of America’s most destructive tree pests. Its larvae kill ash trees by tunneling into the wood and feeding on the tree’s nutrients. The metallic-green adult beetles are a half-inch long, and are active from May to September. The biggest risk of spreading EAB comes from people unknowingly moving firewood or other ash products harboring larvae.
An interactive map of confirmed EAB infestations and stingless wasp release sites in Minnesota is available on the Minnesota Department of Agriculture’s website.