Janesville behind in fight against ash borer: Experts
July 21, 2013
But Janesville may be reacting too slowly to benefit from the new tactics.
After the borer was discovered in Michigan in 2002, methods to fight the borer were unsuccessful. Many municipalities simply put up the white flag and tried to stay ahead of the bug by removing even healthy trees.
Now, experts say treating healthy ash trees could be cheaper in the long run.
“As of today, I think our municipal managers have every tool they need to save their canopy,” said Chad Tinkel, Fort Wayne, Ind., superintendent of urban forestry. The ash borer swept through his city starting in 2006. He figures the last untreated tree will fall to the bug in 2015.
A coalition of experts quoted in a 2011 letter on an emerald ash borer website “strongly endorse” treating trees to maintain healthy canopies.
In many cases, tree conservation is economically and environmentally superior to tree removal, according to the letter.
“However, despite availability of cost-effective treatments, many municipalities, property managers and homeowners continue to rationalize tree removal as the only viable management strategy for EAB.
“This is based on erroneous beliefs that tree removal slows the spread of EAB, or that treatment is not effective, economical, or environmentally sound.”
Deborah McCullough, a leading expert and professor of forest entomology at Michigan State University, was one of the many who signed the letter.
“I think a real danger is being too slow or to think you have years to make these decisions,” she said recently.
She was asked how Janesville should react after the borer was discovered last year.
She and other experts say Janesville is already behind.
“It's real important to get a plan,” McCullough said. “Ideally, you'd have this plan in mind before you find the ash borer.
“If you talk to the city foresters who have gone through an ash borer invasion wave, they will tell you they had a few trees infected; the next year, a few more, and then, all the sudden, the trees were dying at the same time.
“And then, I don't care who you are, you won't have enough money.”
By now, experts consulted say, Janesville should have a tree inventory, should have completed risk and cost assessments and should have started treatments on those trees it wants to save.
What has city done?
The Janesville City Council included $107,000 in the 2013 budget to begin fighting the borer.
About $25,000 of that was to hire a consultant forester. Another $25,000 matched a state grant to treat or replace trees.
Janesville has not yet hired a forester. It lacks a tree inventory and doesn't have a plan. Officials have not reached out to community members to partner with groups or other residents to save trees, another recommendation from those who have weathered the borer.
Janesville estimates it has 15,000 ash trees, about 7,500 of which are in parks and other public places. The remaining are in natural areas. Another 15,000 ash trees are on private property.
Street trees adjoining private properties are the responsibilities of homeowners.
Tom Presny, parks director, has so far spent about $35,190 of the $107,000 budgeted. The city has:
• Removed 80 trees at the cost of $14,000, or $175 a tree. The city allowed residents to haul away the dead wood to lessen the cost.
Presny said he chose trees in prominent locations that were growing in utility lines or were unhealthy to increase community awareness of the borer. Some residents, though, said the choices appeared random and that at least some of the trees were mature and healthy.
• Hired through low bid a contractor to inject 64 ash trees with TREE-age at a cost of $8,225, or $129 per tree. A single injection provides at least two years' protection. Presny said that cost was higher than he anticipated; indeed, other officials contacted pay an average of about $70 per injection. The city does not have trained applicators on staff, which would decrease the cost.
• Sprayed 72 trees with imidacloprid, spending $1,800 for the chemicals and another $500 for labor. That's an average of about $32 a tree for one year's protection.
Presny's goal is to treat 200 trees this year using both methods. He has already treated about 136 trees. Presny and another parks worker chose the trees.
• Installed 10 emerald ash borer traps at a cost of $1,000.
• Trained employees, $3,500.
• Hired a summer intern, $2,500.
• Had miscellaneous expenses of $3,665.
In contrast, the city of Milwaukee began injecting its trees several years before the ash borer was discovered in 2012. By then, the city had completed a tree inventory and analyzed the cost of removing trees versus the cost of injecting them.
What experts say Janesville should do
n Act now.
“In all the talks I do, the last thing I'll say is: 'Don't wait,'” Tinkel said. The science and products are out there.
“If you wait until you start seeing trees dying, it's too late. You've lost a significant number you could have saved.
“It can happen very, very fast, especially if you have droughts.”
An “exponential death curve” usually kicks in in the fourth or fifth year, he said.
Fort Wayne lost 8,500 trees during those two years compared to 1,800 in the previous three.
“Just delaying one annual cycle can mean the lost of a significant number of trees,” Tinkel said.
• Create a tree inventory.
You don't know what you should save until you know what you have, Tinkel said.
“The first thing I would do is make sure I had a good inventory of my street trees—how many of them are ash trees, how big, and then what kind of condition they are in,” McCullough said.
"That inventory will show trees that probably need to come down anyway, those trees that have outgrown their spaces, are growing through wires or were damaged at some point and are declining,” she said.
“Whatever you are going to do (for) treatments, you need to know how many trees are involved,” she said.
Presny earlier this year said an inventory is too expensive, although this week he said his crews inventoried the trees they treated and nearby ashes.
McCullough suggested the city recruit volunteers to create an inventory, such as garden club members or retired people. The inventory would include tree size and canopy condition.
“In all honesty, it's not rocket science,” McCullough said.
• Choose the trees to save and treat them proactively, if possible.
McCullough said her research shows the best product is Tree-Age containing emamectin benzoate. One treatment supplies at least two years of protection, possibly three. Some studies suggest a city could treat a tree for 30 years before it costs as much as removing that tree, McCullough said.
In a study published in 2011, McCullough estimated the total costs to remove and replace ash trees in an untreated study community over a 10-year period were $1.9 million. When 20 percent of the trees were randomly treated with emamectin benzoate—the insecticide found in TREE-age—and treatment began one year after introduction, total costs to remove trees and treat them over a 10-year period was $265,271.
TEE-age must be applied by certified applicators. The chemical is injected into the tree with a high-pressure nozzle. It does not leak into the environment or hurt bees.
Less expensive soil drenches and sprays containing imidacloprid work fine when beetles are at low levels and when used on smaller trees, McCullough said. But those products must be applied every year, and the protection is inconsistent as beetle levels increase, McCullough said.
McCullough stressed she does not accept research money from chemical companies.
Studies continue, and treatments may become even more effective in the future, she said. Possibly, a tree owner might use TREE-age every three or four years with a less expensive soil drench in between, she said.
In Fort Wayne, Tinkel's TREE-age cost—he contracted for the service—is about $73 for a 17-inch tree for two years of protection. That same tree might cost a homeowner about $160 to $170 to hire a certified applicator, but cities typically get cheaper rates because of volume.
The cost to remove that same tree is about $750.
Tinkel this year is paying $32,993 to treat 647 trees.
Ash trees had represented 23 percent of the city's canopy, and Tinkel figured they provided more than $1 million in environmental services, including stormwater retention, energy conservation, carbon dioxide removal and value to property and aesthetics.
Fort Wayne opted to save 10 percent of its ash trees because of budget restrictions. It is treating a total of about 1,200 to 1,400 trees.
Trees can be saved by TREE-age even if the canopy is half-dead, but Tinkel said he doesn't recommend that past 30-percent of die off. The ash will not replace the dead areas, which must be pruned. He questioned the worth of a shade tree that loses 50 percent of its canopy and stressed that is why early treatment is important.
• Consider using the new products to buy time. Even trees that will eventually be removed can be treated to prevent them from becoming liabilities, Tinkel said.
“In a financial sense, I've got a $5 million problem (that can) hit the budget in two to three years or stretch it out for 10 years,” he said.
• Solicit help from the community.
Some cities ask residents or groups to adopt trees that residents would like to save. Residents are often willing to do so, especially if a city tree is near their properties.
In Fort Wayne, Tinkel works with contractors to get low rates in volume for homeowners who then inject their private and city terrace trees.
McCullough said grass root efforts to save trees often form in communities.
Jay Winzenz, acting city manager, acknowledged this week that a community discussion might be needed here to gauge public opinon on how best to proceed with ash tree treatment.
“That discussion has to occur in the context of our financial realities,” Winzenz said.
City comfortable with progress
Presny said he is happy with what the city accomplished this year.
“One of the head-turning points for us is to now see the expansion of the insect around the community and be able to share that awareness with the public,” he said.
“Could we have accomplished more?” he asked.
“We absolutely could have. Had we brought on a consultant, perhaps we would be further ahead.”
But would a consultant's decisions be accepted by the community and council? he asked.
Presny said he is working to keep everybody aware of the problem, learn how to approach it and allow time for the community to respond.
“Are we going in the right direction or not going in the right direction? What are our weaknesses? Is our weakness public information? Do we not have enough public information on our website? Should we be hosting education sessions? What is it we aren't doing?”
“I feel in one year's time--from us requesting $107,000 last fall to getting exposed to this insect now on public land and private land--I think we have learned quite a bit.”
As for the $107,00 budget, Presny said department heads don't expect to fully spend their budgets and turn the excess back to the general fund to be used the next year.
“I'm not intending on saving community dollars; at the same time, I don't want to waste community dollars, either,” he said.
“I've lived through public cuts, and I want to be prudent about how we spend that money and make sure it's with good intention and proper authority.”
He said the next phase of his plan would be aired during 2014 budget discussions in October.
Presny said he is familiar with the strategy of treating trees as an alternative to removal.
“It's a matter of our learning curve and what the community reaction is,” he said.
Still, he believes he has time, adding that he believes the number of trees infected now is only in the dozens.
“The fire is going to rage in the years ahead,” he acknowledged.