This month, St. Louis foresters will start chopping down about 13,000 ash trees on public property to stay ahead of the invasive emerald ash borer, a destructive pest that drains the life out of ash trees.
Nearly one out of five trees on city streets are ash trees. City Forestry Commissioner Skip Kincaid doesn’t deny that some residents may find the change startling, but the damage the emerald ash borer has caused to other cities across the country is no small matter.
“It’s going to be devastating,” he said. “You know, we’re going to see a lot of street trees that die.”
In the St. Louis area, the pest was first spotted last year in north St. Louis. It has now spread to 28 counties in Missouri, most recently to Franklin County.
Quarantine means that they’re regulating the movement of any potentially exposed wood — so any part of an ash tree, firewood, etc.
The emerald ash borer was first discovered in Wayne County (in the southeastern part of the state) in 2008, prompting the Missouri Department of Agriculture to keep any potentially exposed wood from ash trees — including firewood. After other Missouri counties reported the pest, the USDA’s Animal and Plant Health Inspection Service put a quarantine on the entire state in 2013.
An adult emerald ash borer lays its eggs on the bark of the tree. When the larvae hatch, they bore inside and feed on the tissues of the tree that are critical in transporting nutrients and water. Eventually, the disruption causes the tree to wither and die. The dead trees pose a public safety hazard, since they can topple over streets and property.
St. Louis will replace removed trees with 40 different species in an effort to increase biodiversity, said Kincaid, who has worked on emerald ash borer management in other cities.
Officials also decided earlier this year to save about 1,000 ash trees on public land using an organic chemical treatment. The effort, which began in June, was reserved for trees that stood the best chance of surviving.
In the meantime, Kincaid stresses that residents who have an ash tree in their yard should consult a professional arborist about treating the tree, or have the tree removed and replaced.
“We don’t want to scream the sky is falling,” Kincaid said. “We want people to learn about the insect and learn about what it means for ash trees in their yard.”
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