Country Club Lane appears to be ground zero for the emerald ash borer in North Riverside. Though local officials are careful to say they’re not sure if the problem is the emerald ash borer or another pest, ash trees have begun to show signs of dying back.

And on Country Club Lane, a short, quiet street carved out of the eastern border of the Riverside Golf Club, the die-back is particularly noticeable.

“We’re not 100-percent certain,” said Public Works Director Tim Kutt, “whether they are American ash borer or emerald ash borer. Either way, those trees are certainly struggling.”

In the past week, ominous dark blue “X” marks have been spray painted on 10 ash trees on the public parkways, representing about half the parkway trees on the street. In all, according to Kutt, 15 ash trees are showing possible signs of emerald ash borer infestation.

Scott Schirmer, the emerald ash borer program manager for the Illinois Department of Agriculture, has worked with Kutt — one of the state’s earlier proponents of chemically treating ash trees to prevent the spread of the emerald ash borer — for the past six years or so. He’s seen what’s happening on Country Club Lane, and believes it’s the work of the emerald ash borer.

“I think there’s no denying that,” said Schirmer. “I think those trees are infested.” 

In addition to the ones on Country Club Lane, there are a few on Forestview Drive and at least one on Northgate Avenue near Cermak Road. The common denominator for those locations is that all of those areas are near places — the Riverside Golf Club, Woodlawn Cemetery and Cook County forest preserves — hit hard by the emerald ash borer in recent years.

Those trees marked for removal will likely be cut down in the next couple of weeks, said Kutt. After they’re removed, the trees will be inspected to see if, in fact, the emerald ash borer was responsible for the die-back. 

That’s going to alter the landscape on County Club Lane.

“We’re heartbroken,” said one resident of the block who declined to give her name. “This block has such a great canopy. Now all that is going to change.”

Until 2014, North Riverside’s ash tree population has been relatively untouched by any type of infestation. According to Schirmer, North Riverside is quite possibly the last community in Cook County to be confirmed positive for the emerald ash borer.

Meanwhile, all around the village, the emerald ash borer has killed hundreds of trees.

The pest was introduced into the United States from Asia in 2002. Michigan was the first state to see widespread deforestation, but the ash borer has migrated now to a large portion of the Midwest, eastern U.S. and parts of Canada. It’s responsible for the loss of tens of millions of ash trees in the past decade.

The adult emerald ash borer, which is about a half-inch long, lays eggs in the bark of a tree. The larvae burrow under the bark into a nutrient-rich area between the bark and the flesh of the tree, carving out “galleries” that prevent the spread of nutrients from the roots to the branches.

Riverside first saw evidence of the emerald ash borer in late 2011. By mid-2012 the pest was found infesting trees in Brookfield. Since then, those villages have begun removing ash trees wholesale, with number of trees exhibiting the classic die-back symptoms of the emerald ash borer growing each year.

North Riverside’s ash trees, however, resisted. That’s due in large part to the village chemically treating every one of the nearly 500 ash trees on public property annually. Kutt instituted the program about six years ago. 

Until 2014, very few ash trees exhibited signs that the ash borer might be present. Kutt estimated he spends about $12,000 per year drenching the soil at the base of each tree with a pesticide called Merit. Kutt annually consults with the Illinois Department of Agriculture to evaluate the village’s ashes and confirm whether it’s prudent to keep chemically treating the ash trees.

Last year, North Riverside removed two ash trees, said Kutt. Those were later found to be infested by the American ash borer, he said.

The chemical treatments, said Schirmer, likely prolonged the lives of the village’s ash trees. The treatment may have slowed the death of trees already infested when the treatments began. Or, he said, it could just be that the village’s ash trees are getting older and are not fully absorbing the chemicals through their roots.

The area surrounding Country Club Lane, the Riverside Golf Club, has been dealing with the emerald ash borer for about the past four years, said General Manager Kevin Pack.

In the past year and a half, however, the infestation has forced the golf club to remove about 100 of its 270 ash trees, and Pack said he expects another 50 to be removed this winter.

The golf club has used Merit treatments to slow the advance of the ash borer, but the number of infested trees skyrocketed in 2014.

“We’ve spent a lot of money triaging the trees,” said Pack. “But this year it really went south,” Pack said.

One troublesome effect of the tree loss is that some of the ash trees were in play on the course. The loss of those trees will affect how the golf course plays. While new trees will be planted, it’ll take decades for them to mature.

North Riverside started to anticipate the loss of ash trees several years ago by instituting a tree planting program. According to Kutt, more than 300 trees of varying species have been planted throughout the village.

Kutt said he’ll keep treating the healthy ash trees in the hopes that he can spread out the loss of species. But if an ash tree looks like it’s too far gone, it’ll be removed.

“We’re buying time,” he said.