WATERLOO -- Almost every large tree planting project in Waterloo since the 1970s had one common element: plenty of ash.

"We'd throw three or four or five varieties in, but maybe a quarter or a third of the trees we planted would be ash," said city forester Todd Derifield. "They will grow in about any situation. They're a workhorse. They're a survivor."

But with an imported Asian pest now putting those survival skills to the test, city officials say they need to get an accurate count and locate all the ash trees along city streets and in its 52 parks and three golf courses in case they all need to be removed.

City Council members are expected to open proposals Nov. 13 from companies willing to conduct a complete inventory and digitized database of all trees under city control. It's a costly proposition, with estimates in the $140,000 neighborhood, but one city officials say will be vital if the emerald ash borer makes its way to Iowa.

"When this insect arrives in Waterloo it will kill every ash tree in town in a three- to four-year period," Derifield said. "With an epidemic of this magnitude, an inventory of Waterloo's trees and a tree management software package is critical."

The emerald ash borer is an exotic insect from China, Japan and Korea that was discovered in Detroit and Ontario, Canada, in 2002. The beetle's larvae chew up the trees inner vascular system and are fatal to ash trees.

Derifield said experts in Michigan, where cities spent millions to remove the dead trees, have said a comprehensive inventory is the top priority for any preparedness plan.

"In the early 1980s the city did a partial inventory and it was estimated that we had about 17,000 trees just along the streets and not counting the parks," Derifield said. "We've probably got 20 percent of our trees that are ash."

The inventory will pinpoint exact locations of the trees and include data on its size, species, condition and maintenance recommendations.

While the primary reason for pursuing the inventory was the ash borer threat, Derifield said it has other applications.

"It's going to help us tremendously in a lot of areas," he said.

Forestry operations will be more efficient when hazardous tree situations found in the inventory can be prioritized by condition ratings, and the trees can be found more easily by crews getting work orders. City liability exposure would be reduced based on having accurate records and a proactive tree maintenance program. Customer service will be better because accurate information on a specific tree will be available when residents have questions.

"It will make my job easier when somebody calls in with questions about a tree," Derifield said. "I can look up the tree and answer those questions more intelligently."

Mayor Tim Hurley noted the city applied to the Black Hawk County Gaming Association for a grant to help pay for the inventory project.

"I think the ash borer problem gets everybody's interest up, and we'll look for other ways to fund the project if we don't get it from the gaming association," Hurley said. "We know cities of our size have had to spend $4 million to $6 million dealing with (ash borer infestation). It is extremely important."

Both Waterloo and Cedar Falls have banned the planting of any more ash trees along public streets. Both cities and the state have joined in urging people not to transport firewood or similar items back to Iowa from infected states.

Cedar Falls Parks Division Manager Mark Ripplinger said his department was not gearing up for a similar inventory project.

"We're very fortunate, because about 10 years ago a (University of Northern Iowa) biology class did an inventory of all our street trees," Ripplinger said. "It might be a little outdated but we think this would give us a head start if the ash borer shows up."

The inventory proposed in Waterloo and ban on ash plantings are just two steps in the preparedness planning.

The city is continuing to update its forestry equipment. Following the inventory, a plan will be developed in case trees must be removed, which could involve hiring additional forestry staff and/or engaging private contractors.

Forestry crews currently remove about 100 trees a year. It is estimated the city would need to remove 2,000 trees annually if the ash borer arrives.

Contact Tim Jamison at (319) 291-1577 or tim.jamison@wcfcourier.com.