Shots may save W.D.M. trees from ash borer

The emerald ash borer has not arrived in West Des Moines, but city officials are continuing to examine and adopt new ways to prepare for the inevitable infestation.

The city's initial management plan to confront the wood-boring species called for removing all 1,100 of the city's ash tree inventory over about a four-year period "regardless of location, current condition or benefits provided."

But this week, city officials said new data about an alternative treatment method will allow them to keep some trees. A product called TREE-age, which is a trunk-injected insecticide, has been used effectively in many cities, including Milwaukee, said John Olds, West Des Moines' urban forestry supervisor.

In general, healthy adult ash trees — those showing no sign of decay or root system problems — with roughly a 10- to 12-inch diameter should be able to receive the injection treatment, Olds said.

Woodland Avenue residents Tony and Connie Powers said they were pleased with the modified approach that will most likely give their beloved ash tree a longer life.

They joined about 40 others who live on Woodland Avenue and signed a "tree lovers" petition. Since the late 1980s, the Powerses have watched their tree and others like it form a small forest in their corner of West Des Moines.

"We have such a beautiful canopy of ash trees. That's one of the significant features of our street. Can you imagine if the city were to cut down all of our ash trees? It would just leave the neighborhood with a barren look," Tony Powers said.

"Everyone loves this street," Connie Powers said as she stood near an ash tree that hangs over Woodland Avenue.

The West Des Moines City Council this week discussed the emerald ash borer during a workshop.

Emma Hanigan, an urban forestry coordinator at the Iowa Department of Natural Resources, told city officials that they were ahead of many other Iowa communities in their preparations for the insects. "There still are some larger communities that have not put together a plan, and there are many communities that do not have a tree expert," Hanigan said.

There are 52 million woodland ash trees and 3.1 million urban ash trees in the state, according to the Department of Natural Resources' website. The infestation has occurred in 13 counties, with the most recent occurring in Story County in August.

West Des Moines' decision to use a pesticide is similar to approaches adopted in Johnston and Burlington. But Hanigan said smaller communities have not been able to prepare and prolong the lives of ash trees. For example, Mechanicsville in Cedar County and other communities with populations of fewer than 5,000 people are "relying on very limited city staff," Hanigan said.

West Des Moines budgeted $370,000 for the emerald ash borer management plan for the current fiscal year. The full plan is expected to span six years at a cost of roughly $1.7 million. A significant investment was made by officials when they brought on Olds, a full-time urban forester.

Olds said he plans to gather a new inventory of ash trees in the next few months. By mid-2015, city staff will most likely be out on the streets, carrying out the pesticide treatment on ash trees. Residents will be also notified of a more specific set of criteria about which trees are eligible for the injection method.

"They really have to pass an eye test. It's not rocket science," Olds said.

The city will plan to cover the cost of injections for trees that meet the criteria that are in the public right of way, which would most likely include many of those along Woodland Avenue, Olds said. Costs are not projected to increase with the new strategy, officials said.

Olds said he has been in touch with Arborjet Inc., which could offer the city a bulk price for the product and application equipment. A tree 20 inches in diameter costs about $140 to treat for a two-year period, Olds said.

"We're saving the ones that will be around for a while," Councilman Rick Messerschmidt said after the meeting.

Officials said they would also seek out vendors that could offer residents a better rate to treat smaller trees. Reputable tree firms would most likely advise residents of the risks associated with keeping a young ash tree versus planting another type, officials said.