Based on what they've learned from other cities, Lincoln leaders know that all untreated ash trees here will be dead within 15 years once the emerald ash borer moves in.
“And the clock is probably ticking,” said Mayor Chris Beutler at a Thursday news conference releasing the city’s proposed plan for surviving the devastation wrought by the tree-chomping beetle.
The plan — estimated to cost about $22.8 million over 15 years — includes removing and replacing about 1,000 public ash trees each year, starting with young trees and sick, older trees.
Treating trees with chemicals can also help prolong their lives. In addition to treating some trees using city funds, the plan calls for creating an adoption program in which Lincoln businesses, organizations and individual residents could pay for the treatment of specific public ash trees.
And a volunteer tree-trimming program would enable residents to help the city keep up with pruning the hundreds of young replacement trees.
Last year, the city removed and replaced almost 600 ash trees. Its current emerald ash borer-related budget is $950,000 a year.
By systematically dealing with the city’s 14,000 public ash trees over time, Lincoln hopes to ease the death curve for its urban forest and avoid having thousands of dead, dangerous ash trees lining city streets, Beutler said.
"Dead ash trees become very brittle, so if not proactive, we will see a very dangerous situation develop in the city, and that comes with potential city liability," he said. "And waiting to take action will also be much more costly."
A draft of the city's emerald ash borer plan is available online at JournalStar.com and on the city's website (lincoln.ne.gov) and printed copies are available at public libraries and the city Parks and Recreation Department office.
The public can send comments on the Emerald Ash Borer Response and Recovery Plan by March 1 to email@example.com or to the Parks and Recreation office, 3131 O St., Suite 300, Lincoln, NE 68510.
The Community Forestry Advisory Board will hold a March 13 public meeting on the plan. The meeting, in the Parks and Recreation Department offices, begins at 4 p.m.
The emerald ash borer has been officially found in Greenwood, about 15 miles from Lincoln. But experts believe the bright-green insect has already arrived in Lincoln.
The adult insect feeds on leaves, first at the top of the tree, so yellowing in the top of the canopy top is one sign of a problem. But the larvae, which feed just under the bark, kill the tree by cutting off water and nutrients, said Parks and Recreation Director Lynn Johnson. The tree dries out and dies from the top down.
About 12 percent, or 14,150 of the city’s public trees — along streets, in parks and on golf courses — are ash trees, based on a recent inventory.
The city probably has another 40,000 to 50,000 ash trees on private property, based on a Nebraska Forest Service estimate.
Parks and Recreation will host workshops and post information on the city website to help homeowners identify ash trees and the emerald ash borer. Landowners are responsible for trees on their private property, including removal of dead, dangerous trees.
The city also plans to have grants and partnerships with community organizations to help low-income property owners with the cost of removing trees.
Johnson said the city has been adding staff and equipment for the past year to deal with the ash borer.
Those crews mainly focus on trees that are less than 18 inches in diameter. The city wants to remove and replace those first, in order maintain the canopy of older, larger ash trees for as long as possible.
That work is keeping them busy already: Neighborhood groups wanting younger street trees removed have the crews booked for 2018 and part of 2019.
Other neighborhoods interested in the program can call the community outreach forester, Lorri Grueber, at 402-441-9461.
The city will contract with private companies to remove larger trees, plant replacement trees and apply chemical treatments, based on the proposed plan.
In order to help minimize extortion and price-gouging during the epidemic, the city will provide a list of licensed tree service companies with demonstrated knowledge of the emerald ash borer, according to the plan.
The city is also exploring ways to use ash wood, including a potential partnership with Lincoln Public Schools and the Nebraska Forest Service in which high school students would learn about milling logs for lumber and use ash wood in shop classes. The city may also partner with the state Department of Correctional Services, which uses inmate labor to manufacture furniture.
Lincoln would continue to provide wood chips to community organizations.