Citizen Staff/Dan Baulch
City of Beaver Dam Parks Supervisor John Neumann inspects one of Vo-Tech Park's 21 ash trees. Neumann said it's only a matter of time before the emerald ash borer reaches Beaver Dam.
When environmentalists talk about going green, this isn't what they have in mind.
Over the past decade, the emerald ash borer has infiltrated 11 states, including Wisconsin. City of Beaver Dam Parks Supervisor John Neumann says it's only a matter of time before Beaver Dam becomes home to the insect which has already killed 40 million ash trees around the country.
"The bug is here in Wisconsin and it's not going away," Neumann said. "It's not a matter of if, but when it comes to Beaver Dam. But the more time we can buy without it spreading, the more time we can find a way to manage it."
The emerald ash borer is a shiny green beetle native to Asia. It was accidentally introduced to the United States in the 1990s and discovered in Michigan in 2002. The insect lays its eggs in crevasses of ash tree bark, and the feeding larvae effectively strangle the trees by consuming the portions essential for the transportation of water and nutrients.
Neumann said the emerald ash borer has been on his radar the past four years, thanks to education from the U.S. Department of Agriculture and urban forestry. The topic hit close to home last August when it was confirmed the borer had infiltrated Wisconsin's Ozaukee County.
There are currently hardwood quarantines in Sheboygan, Ozaukee, Fond du Lac and Washington counties aimed at eliminating the spread of the borer. The quarantine restricts the transport of hardwood firewood, ash nursery stock or ash logs or timber out of those counties.
"It's confirmed in Ozaukee County, but the thing is it takes about five-to-seven years before you can see the effects of the borer," Neumann said. "It could be in Beaver Dam already and we might not even know it. We just did $30,000 worth of tree work doing trimming and removals and didn't see it. But that doesn't mean they're not here because they're so hard to detect early on. Once you see the effects, the bug has already been there five, six years."
If the borer reaches Beaver Dam, it will have plenty to feed on. There is a significant population of ash trees in the city, from parks to private residences. Coincidentally, when Dutch elm disease wiped out those trees in the 1960s and 1970s, ash trees were a popular replacement. In fact, Vo-Tech Park was adorned with 21 ash trees while Edgewater Park is 90 percent ash.
"To lose them would be devastating," Neumann said.
So what can the city of Beaver Dam do to save its significant number of ash trees? Nothing with a guarantee of success, according to Neumann.
The parks department began its ash strategy two years ago when it stopped planting the trees around the city. There are 42 white ash trees in the city's nursery, and they will probably remain there. Instead, Neumann has planted elms, Norway maples, Kentucky coffee trees, pin oaks, Japanese tree lilacs, hackberrys and butternuts.
"Diversity is key," Neumann said. "If something attacks your trees, it won't wipe them all out."
The department is also being proactive and removing some ash trees that already look unhealthy or have been injured over the years. As is Neumann's policy, any tree removed is replaced if at all possible with another species.
On a limited basis, ash trees will be pumped with insecticide in an effort to save some of the city's best specimens.
"If we have some really, really nice trees that are big and flourishing, we might try to protect them and hang on to them," Neumann said.
But the strategy is a gamble, and a costly one at that. The success rate according to University of Wisconsin entomologists is only 80 percent, and the treatment can cost between $40 to $60 or more per tree every other year.
"The entomologist lab is telling us to not even bother treating trees until there's been a sighting within 10 miles," Neumann said. "Otherwise you're pumping a lot of costly insecticide for nothing."
Although it's impractical for the city to treat every one of its trees, Neumann said he understands the private property owners' wish to protect their ashes.
"If I had healthy ash trees in my yard I wouldn't want to lose them either. But you have to be careful. There will be companies, some of them reputable, coming to town knocking on your door saying they want to treat your trees, which is fine. But if they say they can guarantee success, I'd hang on to my wallet and show them the road, because that's just not reality. The success rate isn't there. Maybe something in the future will come up, but that's not where we are now."
While scientists work on better solutions, whether it be more effective insecticide, the possibility of introducing predators of the emerald ash borer or even developing borer-resistant strains of trees, it is important that everything is done to keep the insect from spreading.
The key to that, according to Neumann and urban forestry officials, is to refrain from transporting wood from quarantined areas.
"The ash borer might move half a mile a year on its own," Neumann said. "When you suddenly have sightings come up in random areas, that's not natural movement. That's firewood movement, chip movement and infested nursery stock. There needs to be public education on not moving firewood and only buying local or just keeping away from ash completely right now.
"That will give us the time we need to find a better solution."