Just as holiday campers and bugs are about to emerge for the season, Gov. Mark Dayton has declared Sunday through May 28 as Emerald Ash Borer Awareness Week in Minnesota.

Background: The bug, which has destroyed millions of ash trees across the United States and Canada, was first detected in Minnesota in May 2009. It has been found in Hennepin, Ramsey and Houston counties. It did not expand as widely as expected last year, said Minnesota Department of Agriculture entomologist Mark Abrahamson, but a not-very-cold winter may have allowed more larvae than usual to develop toward adulthood. Adults "bore" out of ash trees in mid- to late spring.

What's at stake: Minnesota has nearly 1 billion ash trees. The species is native to Minnesota but was also a popular replacement for elm trees in urban areas after the Dutch elm epidemic of the 1970s. In Minneapolis and St. Paul, more than 20 percent of the trees are ash.

Key message: Don't move firewood; buy it or gather it where you're camping. Look for a Minnesota Department of Agriculture "Safe to Move" label on sold firewood. Transport of firewood is considered the key reason for the rapid expansion of the bug's range across North America. The Memorial Day weekend is expected to put thousands of campfire-loving folks on the roads across Minnesota.

What you can do: Identify ash trees and signs of infestation, such as woodpecker damage, die-off of upper branches, sprouts around the trunk and D-shaped holes in the bark, and report them to the Arrest the Pest hotline at 651-201-6684 or 1-888-545-6684. Assess whether any infested trees can be affordably saved.

To learn more: A wealth of information is available at www.startribune.com/a417 and www.emeraldashborer.info as well as by calling the Arrest the Pest hotline.