The emerald ash borer, believed to be the most destructive insect ever to afflict trees in North America, has been confirmed for the first time in Omaha.
The Nebraska Department of Agriculture confirmed Wednesday that the invasive beetle had been found for the first time in the state in Pulaski Park in South Omaha.
The infestation is likely in its early stages since foresters and arborists had been searching for signs of the beetle for several years and had not found any, said Graham Herbst, the eastern Nebraska community forester for the Nebraska Forest Service.
How well-established the beetle has become matters, because it will determine how quickly the infestation marches through the metro area. The beetle kills all untreated ash trees, young or old, healthy or weak. That will be devastating, because ash is among the region’s most plentiful, sturdy native trees.
"We have suspected for a while that it’s in the area," Herbst said. "It’s one of those things: We really wanted to find it, and really didn’t want to find it at the same time. What’s to come is not pleasant."
Foresters estimate that nearly 10 percent of trees in Omaha are ash, according to the Nebraska Forest Service, similar to the statewide average. In some communities, ash makes up 20-plus percent of the trees on public land.
Nebraska has an estimated 44 million ash trees. It is the 27th state to confirm the presence of the pest, the Nebraska Department of Agriculture said.
Eventually, the infestation in Nebraska is expected to cost state and local governments, homeowners and businesses nearly $1 billion. That’s the estimated cost of cutting down and replacing ash trees. Add in the expense of treating trees, and the cost is expected to go higher.
Q&A: The emerald ash borer is here. Now what?
The Nebraska Department of Agriculture issued a quarantine for all of Douglas, Sarpy, Cass, Washington and Dodge Counties. The quarantine prohibits ash tree nursery stock from leaving that area.
The quarantine also covers green ash lumber and any parts of ash trees, living or dead. It also prohibits moving any firewood, wood chips or mulch, of any hardwood species, out of the quarantined area.
In the 14 years since the emerald ash borer was discovered in North America, it has killed hundreds of millions of trees, mostly in the eastern United States. The rapid advance of the emerald ash borer across the country is believed to be due to the transport of infected firewood and nursery stock.
If there’s any good news for those in the Omaha metro area, it’s that the emerald ash borer has been the subject of furious research since it was first discovered in Michigan and Ontario in 2002. Homeowners today have better treatment choices than did those who went through the first wave.
Treatment options involve injections, drenches and sprays, said Mark Harrell, forest health program leader for the Nebraska Forest Service.
Treatment is best done in mid-May to early June, Harrell said, which means the window is nearly closed for this year.
The inability to treat a tree this year should not be viewed as a death sentence for the tree, Harrell and Herbst said.
The emerald ash borer is limited in how far it can fly, so the beetles in Pulaski Park aren’t expected to cause widespread, immediate harm. At best, the beetles there will be able to fly a few miles away. Most will stay in the immediate vicinity of the park at 40th Avenue and H Street.
"It probably hasn’t spread very much because there’s so much material for it to feed on right where it is," Herbst said.
On the other hand, it’s not possible for foresters to know how much beyond the park the beetle population extends, so it’s not possible to define the boundaries of any infestation.
The beetle could be in other areas of the city, too, but so far, no confirmation has been found.
Herbst said local and state foresters teamed up last year to search logical areas of the Omaha metro for the beetle — and found none. That’s another reason to believe that the infestation is in its early stages, Herbst said.
"Logical areas" are along Interstates and highly trafficked tourist sites like the Henry Doorly Zoo, he said. These are areas that receive lots of travelers and recreation vehicles hauling firewood.
In Omaha, evidence of the beetle was found under the most ironic circumstances: during a press conference to announce the city’s plans to battle the insect.
On Friday, a City of Omaha Parks Department crew cut down a diseased-looking ash tree in Pulaski Park to provide the public an example of the types of trees it will remove under its beefed-up response plan.
A parks worker peeled back the bark of the tree. They always do that when cutting down an ash tree, Parks Director Brook Bench said.
When the wood of the diseased tree was laid bare, arborists at the site realized the moment of reckoning had arrived, said Herbst, who was there.
"There were some expletives and some gasps," he said.
The tree’s trunk bore the tell-tale squiggles of the larvae of an emerald ash borer. But to have confirmation, foresters needed to find the beetle itself, or its larvae.
On Monday, foresters found a suspicious beetle among limbs that had been cut down, he said. The beetle was sent via overnight, express mail to the U.S. Department of Agriculture for confirmation.
The confirmation of emerald ash borer continues a string of disappointing news for the state’s trees. Pine wilt already has wiped out most of Nebraska’s Scotch pines, the Missouri River flood of 2011 killed many of the trees in the river valley along the state’s eastern border, and drought has thinned out the already thin canopy in the heart of the state.
If Nebraska is to continue to have a vibrant stock of trees, it will need to undertake an effort equal to the threats trees are facing, said Eric Berg, community forestry and sustainable landscape program leader for the Nebraska Forest Service.
This includes planting a greater diversity of trees than has typically been the case in communities, he said.
Complicating the decision is climate change, he said. Nebraska’s climate is changing so rapidly, it’s not clear what type of tree will survive and thrive for decades to come.
The state’s average temperature is rising, the growing season is lengthening, and Nebraska is expected to become more vulnerable to extreme drought and extreme precipitation, research has shown. While the increasing warmth would normally make the state more hospitable to southern trees, that’s not a given, Berg said, because Nebraska remains prone to deep freezes in winter that would kill those trees. Further muddying the decision is the widening variety of pests and disease moving into the area with climate change.
So, while the state is experimenting by planting trees from the Southern Plains, it’s also looking at those that thrive in northern states — and from other areas of the globe, particularly China, that have a similar climate, he said.
"We don’t have a good solid answer for that, so the answer is going to be, let’s plant a lot of different types of trees," he said.
By: Nancy Gaader (World Herald).
Contributing: Christopher Burbach (World Herald).
Photo: KCCI.
Review: Emerging Market Formulations &
Research Unit, FLAGSHIP RECORDS.
For The #FacebookTeam