What's up with all of those trees wrapped in yellow caution tape?

Drivers in Lincoln last week may have thought a crime occurred at several spots downtown and elsewhere.

But if they looked a little more closely, they saw a sign that read "Burn It Where You Buy It."

The tape and the signs are part of a state and national campaign to raise awareness about the threat of the emerald ash borer - and what people can do to delay the insect's appearance in Nebraska.

"We do not have EAB in the state, yet," said Steve Rasmussen, Nebraska Forest Service district forester. "I say 'yet' because we think it's coming."

The invasive insect that attacks and kills all North American ash species was found recently near La Crosse, Wis., about 300 miles from Nebraska - and the closest so far, he said.

Nebraska is one of 18 states participating in the campaign to stop the beetle's path of destruction. Gov. Dave Heineman signed a proclamation declaring last week Emerald Ash Borer Awareness Week.

The beetle disrupts ash trees' ability to transport water and nutrients.

Nebraska has an estimated 37 million ash trees in towns and cities, as well as forests and conservation plantings. The trees will all be at risk when EAB arrives, Rasmussen said.

Green ash trees are native to Nebraska, and white, black and autumn purple ashes are popular landscape trees.

As part of the campaign, yard signs and posters placed near ash trees encourage people to buy and burn firewood locally.

"We want to keep EAB out of Nebraska as long as possible, and encouraging people to purchase locally harvested firewood at their destination is one of the best defenses we have against this pest being brought to our state," Rasmussen said.

First detected in southeast Michigan in 2002, the emerald ash borer infestation has spread throughout Michigan, as well as to Minnesota, Illinois, Indiana, Ohio, Pennsylvania, Maryland, West Virginia, Virginia, Missouri and Wisconsin. It also has been detected in Ontario and Quebec in Canada.

In all, the emerald ash borer has killed about 50 million ash trees.

Firewood quarantines exist in Illinois, Indiana, Maryland, Michigan, Missouri, Ohio, Pennsylvania, Virginia, West Virginia, Wisconsin and New York.

While there are no mandates in Nebraska, people are being asked not to transport firewood.

State forestry agencies in Kansas, Nebraska, North Dakota and South Dakota have worked together for the past couple of years to prepare for the arrival of such invasive species as the emerald ash borer by assessing tree resources, determining and addressing potential threats, creating public awareness and promoting species diversity.

The project, the Great Plains Tree and Forests Invasives Initiative coordinated by Rasmussen, is funded by a U.S. Forest Service grant and matching state funds.