Wisconsin Strategy Shifts to Protect Ash Trees
Posted on: Saturday, 10 May 2008, 15:00 CDT
By LEE BERGQUIST
Many healthy ash trees in Wisconsin could escape the chain saw under a new strategy aimed at fighting the emerald ash borer.
The plan will be released in a few weeks as state officials adjust their planned response to what they see as an inevitable invasion by the destructive beetle.
The old approach, written in 2006, leaned heavily on a national scientific advisory panel that recommended cutting all ash trees within a half-mile of an infestation in newly found outbreaks.
But officials said last week said this won't happen in all cases.
Wisconsin has 725 million ash trees, with an estimated 5 million in cities and villages, according to the state agriculture department.
The emerald ash borer was first discovered in southeast Michigan in 2002 and is blamed for killing more than 30 million trees from Maryland to Illinois. It is believed to have come from Asia on wooden packing material.
"We aren't going to be locked into one option," said Brian Kuhn, plant industry bureau director for the Wisconsin Department of Agriculture, Trade and Consumer Protection.
The state is changing its strategy because of advances in pesticides that could protect infected trees, especially in residential areas.
And officials want their planning to reflect how governments today are adjusting to managing outbreaks.
The leading federal agency, the Animal and Plant Health Inspection Service, is in the midst of rewriting its strategic plan as well, a spokeswoman said.
Early on, the agency pushed for large-scale cuts of ash trees, but it doesn't make such mandates today.
"We have eliminated the word required from our vocabulary," spokeswoman Sharon Lucik said.
The federal government spent $130 million to combat the emerald ash borer from 2003 to 2007, Lucik said.
Reluctance to cut
As more is learned about the beetle, states have grown more reluctant to cut seemingly healthy ash trees a half-mile from an infested tree.
Research has shown that some emerald ash borers will fly more than a half-mile. And when the beetles burrow into firewood or other wood products, humans can unwittingly move them anywhere.
In Illinois, where the emerald ash borer was discovered in June 2006, the agency recently completed its first mass eradication of ash trees.
More than 900 ash trees -- many of them less than 6 inches in diameter -- were removed from within and near an interchange of I- 80 in Peru, southwest of Chicago.
"It was a unique situation," said Warren Goetsch, chief of environmental programs for the Illinois Department of Agriculture.
Most of the trees were on state land, and because they were at the junction of two major roadways, the beetle could have hitchhiked quickly to new areas.
"In other cases where we have found detections, it has been more of a case of removing the known infested trees and not going any further," Goetsch said.
The Wisconsin Department of Natural Resources says the cost in other states of eliminating ash trees within a half-mile of an infestation has been about $1 million per site.
How Wisconsin will respond to outbreaks will be spelled out in planning documents, Kuhn said.
Infected trees would be cut, but perhaps in some cases pesticides would be used, he said. An outbreak near a lumber mill would likely be treated more aggressively than one in a remote wetland of black ash. What private landowners say also will be strongly considered.
Promising alternatives
Two or three years ago, there was virtually nothing that could be done to fight the pest. When an ash tree was infected, it was a death sentence.
But two new pesticides are promising developments.
A pesticide marketed under the trade name Safari 20 SG has been granted a conditional-use permit by Wisconsin's agriculture department. It is sprayed on the trunks of trees.
Another chemical known as Tree-age (pronounced triage) is injected into the base of a tree. The product has not been approved in Wisconsin, but if emerald ash borer strikes, officials expect it to be registered quickly.
Both pesticides must be applied by licensed applicators.
"We're really pleased that there are some options out there," said Brian Swingle, executive director of the Wisconsin Green Industry Federation, an organization that represents nurseries, garden centers and other groups.
Swingle said the pesticides wouldn't work for forests, but they could be used in smaller settings.
Wisconsin has been looking for the emerald ash borer since 2004.
This spring, crews are hanging more than 3,500 purple traps in trees in southeastern Wisconsin and other locations.
The agriculture department has cut and stripped 1,729 ash trees between 2006 and 2008 to look for the serpentine patterns of larvae in the tissue of the tree. This included hundreds of ash in metropolitan Milwaukee.
"I'd have to say that I'm surprised we haven't found it yet -- I'm happily surprised," Kuhn said.
State forester Paul DeLong agreed.
"The law of averages says that we will get it," said DeLong, who works for the DNR.
"What we hope to do is, with a public education campaign, is to delay its arrival for as long as possible so that research can catch up and give us time for protection and control and more options."
Firewood is the most feared vector of introduction, and authorities in Wisconsin would prefer that all firewood be bought locally.
IN SEARCH OF THE BUG
The Wisconsin Department of Agriculture, Trade and Consumer Protection has cut and stripped 1,729 ash trees between 2006 and 2008 to look for the serpentine patterns of larvae in the tissue of the tree.
On the Web
For more information on the emerald ash borer, check out the state's Web site: emeraldashborer.wi.gov
Source: Milwaukee Journal Sentinel
 |
 |
User Comments (0)
RSS Feeds