Minnesota issues new rules to stop emerald ash borer

The quarantine applies to Ramsey, Hennepin, Houston, and Winona counties. Ash firewood, logs, wood chips, and nursery trees cannot be moved out of those counties without Agriculture Department permission.

Gier Friisoe directs the plant protection division of the Agriculture Department and said nurseries, sawmills, and firewood dealers are all on board with the quarantine.

"They've all been, for the most part, extremely cooperative and understanding," Friisoe said. "I think they're doing their best to comply and avoid the potential for introducing EAB to other portions of the state."

Friisoe said the agency has worked out some agreements that permit moving firewood.

"There are a number of firewood dealers that have begun kiln-drying their firewood and it's actually become a bit of a marketing tool for them," Friisoe said.

Not only is the wood thoroughly dry, but it's free of all bugs.

The latest ash borer discovery was in Winona County last August; Friisoe said the pest had probably been there for some time. He gave high marks to St. Paul and Minneapolis for aggressively removing infested trees.

Ash borers kill all types of true ash trees. Minnesota has the highest volume of ash trees of any state.