Emerald ash borer is coming. It is has been found in 31 states, including Minnesota, Nebraska and within 80 miles of our border in Iowa. While we haven’t found it in South Dakota yet, it is just a matter of time.
The borer, commonly referred to as EAB, is a relatively small insect. It repeatedly attacks the ash tree, growing in numbers each year and consuming only the layer of tissue beneath the bark that is vital to the tree’s survival. It’s stealthy too, attacking the top of the tree first, so it’s hard to find. The tree dies about seven years after the first attack. Our ash trees, unlike the ash trees in Asia, where the insect came from, are completely defenseless against this insect.
Ash is one of the most abundant trees in South Dakota. It was planted extensively in our communities and in windbreaks after Dutch Elm disease started killing our American elms in the 1960s. It is also native to our state and can be found along our streams, rivers and in our woodlands.
The borer moves from tree to tree by flying. It moves from city to city, and county to county, usually by movement of infested firewood. But it’s also a good hitch hiker, clinging to vehicles as they travel our highways.
One of the things South Dakotans can do before EAB arrives is limit the movement of firewood. If you need to buy firewood, purchase it locally and make sure it was cut locally. If it isn’t local wood, make sure it is certified to be free of insects. If you’re going camping and want to have a campfire, get the wood at the campground and don’t take any wood home with you.
EAB only attacks and kills ash trees, but it will do so indiscriminately. Healthy and unhealthy trees will be lost. We can prepare for the future by removing ash trees that are in poor condition now and replace them with young trees of different types. While it won’t protect us from EAB this time around, increasing the diversity of tree types in our communities and countryside will ensure more resilience to losses from invasive insects and diseases in the future.
For more information on EAB, go to the SD Department of Agriculture website at sdda.sd.gov, under Conservation & Forestry, Forest Health, Invasives.
