St. PAUL, Minn. – The Minnesota Department of Agriculture (MDA) is setting nearly 16,000 gypsy moth traps across eastern Minnesota starting this week as part of its annual program to monitor Minnesota’s forests and urban areas for new infestations of the destructive tree pest.
While emerald ash borer – the state’s other high-profile tree pest – attacks only ash trees, gypsy moth caterpillars devour the leaves of many tree species including oak, poplar, birch and willow. Severe infestations and repeated defoliation can kill trees, especially when the trees are already stressed by drought conditions or other factors. Fortunately, there are several effective treatment options for dealing with gypsy moths – unlike emerald ash borer.
The MDA’s early warning system against the moths is a network of small, gold colored cardboard traps attached to trees or poles. The cardboard traps contain a pheromone to lure in male gypsy moths. Once inside, the moths become entangled in the sticky interior. In mid-summer and again in the fall, workers remove the traps and count the moths inside. When MDA finds a significant number of moths in an area, it moves in to conduct treatments designed to control them.
MDA’s 2009 monitoring program discovered record numbers of gypsy moths moving inland from the North Shore of Lake Superior, but very few in other parts of the state. The 2009 detections prompted MDA to develop plans for control treatments in the spring and summer of 2010 along the North Shore. The treatments decreased the state’s total 2010 gypsy moth counts to less than 10 percent of what was caught in 2009. With the 2011 treatments as a follow-up to that, the goal for this year’s trapping survey is to have equal or lesser total moth counts than the 2010 season.
MDA Plant Protection Director Geir Friisoe said monitoring is a key part of the fight against gypsy moths.
“For nearly 30 years, MDA has been eradicating small infestations and delaying a full-scale invasion of the state’s forests and urban areas,” Friisoe said. “Our efforts have pushed back the full-scale invasion of gypsy moth by years if not decades. Every year we delay the moths’ establishment is a victory for the environment and the economy.”
Citizens are asked not to disturb the traps and to call the Arrest the Pest Hotline at 888-545-MOTH if they would like traps moved or removed from their properties. For more details about the trapping program and gypsy moths, visit the MDA website at www.mda.state.mn.us/gypsymoth.
