EnergyLines October 2016

Emerald Ash Borer claim thousands of trees

Work progresses to keep rights-of-way clear


Each spring, Perry Dow, Hoosier Energy’s vegetation management coordinator climbs into a helicopter and patrols miles and miles of transmission rights-of-way that crisscross southern Indiana and southeastern Illinois. He’s looking for dead trees, overgrown brush or any other vegetation growth threatening to interfere with power lines along Hoosier Energy’s nearly 1,700-mile transmission network.


It’s one of several aerial patrols he makes as the seasons turn to target dangerous trees before the dead hulks topple into power lines and potentially cause an outage or, worse, a fire.


Every growing season brings new challenges, so after several seasons of wet conditions, Dow feared the worst.


What was different this year, though, was not an increase in overgrowth conditions. That spring patrol showed something else. “We identified 900 clusters of dead trees threatening power lines. The largest majority of them were ash,” Dow said.


“After the patrol, I went onto the DNR website and found a map. It was dotted with where the ash borer had hit. And those dots were right in the middle of Hoosier Energy power lines, especially near English and Napoleon,” Dow said.


Why so many dead ash trees? The reason is a pesky beetle called the Emerald Ash Borer. This wood-boring beetle native to Asia first surfaced in Michigan in 2002. It showed up in Indiana in 2004 and has continued a steady destructive march throughout 28 states ever since, killing millions of ash trees in its wake.


According to the United States Department of Agriculture, Animal and Plant Health Inspection, the EAB is responsible for the death or decline of tens of millions of ash trees in North America – the largest plant infestation in history.


The Midwest has been particularly hit hard by the pest.


Professor and Extension Specialist Clifford Sadoff of Purdue University’s Department of Entomology has been studying the problem for years.


There are more than 147 million ash trees in Indiana, he says, and easily about 25,000 or so in or near utility rights-of-ways. All are likely infected. “The first time I saw it, it almost brought me to tears. In 2010, we would look at an area and find 50 good, 50 fair, 50 poor trees. By 2012, 80 percent of the trees had passed into the poor category. It was  that dramatic.” 


Sadoff estimates that the beetle could kill most of them – at a die-off rate that keeps doubling every year. “As sure as night turns into day, the problem will get worse before it gets better.”


For Hoosier Energy and member systems, the numbers keep climbing.


“We’re averaging 85 trees that are eliminated each week,” says Brady Mann, Manager of Delivery Services. “An ash tree killed by the EAB dies quickly and will fail at the base, creating a real hazard for power lines.”


Dave Barton, Manager of Operations & Engineering for Clark County REMC, agreed. “We have ash trees on every circuit, every sub. A few years ago, it wasn’t so much of a problem. But now, they’re dying as we speak.”


Often located outside a traditional utility right-of-way, a mature but dying ash tree with height and breadth can threaten cooperative power lines inside the right-of-way. Barton says recent outages on the Clark system have been due, in part, to diseased ash trees located outside the traditional right-of-way.


The scale of the problem is enormous and affects nearly every member system with those on the eastern side of Indiana hit the hardest. To counter the threat, Hoosier Energy and member systems are proactively working to remove the infected trees in a timely, cost-effective way consistent with state and federal regulations and quarantine notices regarding the infestation.


Removing these beautiful trees is not an easy decision, especially for homeowners. David Vince, General Manager of Clark County REMC, says he has more than 30 trees on his property that have fallen to the disease.  “I hated to see them go, but we had to take them down.”


“We’re taking a planned approach, scheduling crews to take them down and moving on,” Barton says. “We’re also working with the county to help us with cleanup on the roads. Homeowners, when we approach them, understand. We’ve been successful so far.”


In the long run, Dow says, developing a strategy to stay ahead of the destruction prevents outages, which would be a far greater cost than removal. “If we don’t get this taken care of, the dangers, and costs, will just skyrocket.”


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