An insect that has the potential to kill millions of trees in Nebraska and southwest Iowa has been found north of Kansas City, Mo., bringing into sharp relief an imminent threat to the region's canopy.
Scientists have confirmed that a dead ash tree in a Parkville, Mo., neighborhood was carrying the emerald ash borer, said Justine Gartner, forester with the Missouri Department of Conservation.
Gartner said several other trees in the neighborhood show signs of ash borer infestation.
Eric Berg, program leader for community forestry at the Nebraska Forest Service, said the discovery has heightened worries in Nebraska about the potential for an explosive infestation.
Ash trees make up 7 percent to about 40 percent of the canopy in Nebraska communities, he said. And because the tree is native to this area, it's found by the millions in forested areas and windbreaks.
The emerald ash borer is an exotic pest that was first discovered in Michigan in 2002 and has since killed an estimated 50 million trees in more than a dozen states.
The insect can fly only a half-mile or so from a tree, so its rapid spread is occurring via infected firewood and nursery stock. This is why the movement of nursery stock has been restricted and homeowners and campers are being asked to burn only local wood.
Gartner said the nearest known infestation to Parkville is 365 miles away in southeast Missouri.
Mark Harrell, program leader for forest health at the Nebraska Forest Service, said the Missouri discovery makes it more urgent that Nebraskans prepare for the arrival of the emerald ash borer.
Once established, the insect can move quickly through the ash tree population, leaving a city with a hazard and expense: more dead trees than it can afford to cut down.
Despite that threat, Berg said, foresters advise against preventive treatment of trees until an infestation has been confirmed within about 15 miles. That's because of the threat of collateral harm from chemical treatment, especially during a time of drought, Berg said.
The best thing homeowners can do for their trees is to take good care of them, watering deeply and intermittently during the drought.
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