EAB Update from MN Department of Agriculture

Minnesota’s trees and forests are under attack from the emerald ash borer (EAB) beetle, which destroyed tens of millions of ash trees. Minnesota currently has a quarantine placed on Ramsey, Hennepin, Houston, and Winona counties to help slow the spread of EAB to other areas.

Our state has the highest volume of ash trees in the U.S., with almost a billion forestland and urban trees. Ash trees provide substantial economic and ecosystem benefits to taxpayers, ranging from increased property value to stormwater mitigation to decreased energy demands.

Cold snap is no snow day for EAB management
Recent media reports have described the potential impact of extreme cold weather on EAB. A recent study has found that some EAB larvae begin to freeze and die when temperatures within trees reach -20°F, and that survival is very unlikely when temperatures reach below -30°F. Wind chill does not affect EAB.

The study authors speculate that temperatures within known EAB-infested areas in Minnesota have been cold enough in recent weeks to cause a moderate to high level of larval mortality. This winter mortality should slow EAB population growth in these areas, but it is probably not enough to justify changing management plans. EAB populations will likely recover and should still be expected to grow to tree-killing levels.

Is EAB on the move?
Currently, no new counties have been quarantined for EAB in Minnesota. However, EAB has been detected in new areas and cities within the current quarantined counties. In September 2013, EAB was found in Superior, Wis., near Duluth.

How does Iowa’s state EAB quarantine affect Minnesota cities?
As of Feb. 4, 2014, the state of Iowa established a state quarantine for EAB, which may affect Minnesota’s southern border cities and counties. The statewide quarantine for Iowa restricts movements of ash material outside of the state.

Therefore, Minnesotan cities bordering Iowa must be aware that ash wood movement from Iowa is prohibited without a compliance agreement from the U.S. Department of Agriculture (USDA). For questions and additional information contact the USDA’s David Ward at (952) 814-1084 or David.Ward@aphis.usda.gov.

MDA-certified firewood
The transportation of firewood is a leading cause for the accidental introduction of harmful tree insects, such as EAB, and diseases to new areas. Insects like EAB can hitch a ride on cut wood from both living and dead trees and are often hiding under the bark. Studies have shown that EAB can emerge from wood for two years after it has been cut.

One of the most effective ways to stop EAB is to not move firewood or any ash tree material. In Minnesota, hardwood firewood that is safe to move across the state and allowed to move out of quarantined counties is wood that is certified by the Minnesota Department of Agriculture (MDA) and is labeled with a seal. Moving uncertified hardwood firewood out of a quarantine is illegal and is punishable by up to a $7,500 fine per violation per day.

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