Living on the Great Plains, most of us know that trees are a precious commodity.
That’s why a small beetle, which is eating it’s way through the tree stands of the eastern U.S., is such a threat. The emerald ash borer has already been found in ash trees in eastern South Dakota.
One Black Hills city official describes the ash borer invasion as a slow-moving wildfire, moving across the landscape, destroying trees as it goes.
“Any ash tree is vulnerable to the borer. There is not an ash tree that grows here that is resistant.” said Rapid City Parks and Recreation’s Andy Bernard.
Ash trees are native to South Dakota, and their golden leaves are familiar autumn site in towns across the state. Up until now, ash trees have been fairly resistant to the native bugs that attack from time to time. But not this time.
“Emerald ash borer doesn’t work that way. Our trees have no natural defenses, so they pretty much just eat them all,” Bernard said.
And they are moving west.
“It is going to happen, and it’s going to be soon.” Hermosa Board President Dan Holsworth said.
Holsworth is one of the many city officials tasked with dealing with the coming invasion. They are making plans and fast.
“Within two years we’re going to see that problem existing here,” Bernard said.
Some cities are going to treat trees they want to keep. Others are planning to cut down some ash trees to make it difficult for the beetle to spread.
In Rapid City for example, the management plan is a combination of treatment and triage. It’s a big job. Rapid City, like most South Dakota towns has a lot of ash trees.
“Total…forty thousand. It’s a best guest estimate right now. We’re working on an inventory of all of our park trees,” Bernard said.
Like most west river towns, Hermosa is cutting ash trees as well. To stay ahead of beetle invasion, city officials say it’s important to eliminate as many food sources, and sources of infestation as possible. But Hermosa is taking steps to immediately replace the trees they cut down.
“We’re going in and putting different species in that will not have that problem,” Holsworth said.
The emerald ash borer invasion isn’t just affecting city park and street departments. Private landowners will be facing the same threat, and will have to make the same choices. Does one cut down the trees or try to save them.
“You can treat your trees once the ash borer is identified in the area. We don’t recommend treating any trees until the ash borer infestation is identified within fifteen miles,” Bernard said.
That process isn’t cheap. A treatment for a single tree runs from $120 to $250. Holsworth says it’s still a cheaper than cutting down, removing, and replanting a new tree. He says some ash trees in South Dakota are 50 to 100 years old, and their property value in some neighborhoods could be calculated in the tens of thousands of dollars.
“So it’s going to be a matter where the homeowner is going to have to be the individual to decide, yes, I want to save this tree,” Holsworth said.
And it’s not just an economic decision. We all have memories of backyard swings and summer picnics beneath stately old ash trees. These sentimental factors will be also part of the decision as to what steps to take to combat the coming invasion.
The emerald ash borer has now invaded eastern South Dakota, Nebraska, and parts of Colorado.