By Ben Lawson
Last week, Sevier County joined several other East Tennessee counties under an emergency quarantine after the discovery of a disease that kills walnut trees.
The Tennessee Department of Agriculture announced that traces of Thousand Cankers Disease had been found in Sevier and Loudon counties. First discovered in Knox County in 2010, the disease’s spread led to Anderson, Blount, Knox and Union counties being quarantined.
“We will continue to survey our forests and work to help slow the spread of the disease,” said TDA Plant Certification Administrator Gray Haun. “We are working with stakeholders to help educate citizens on the symptoms of TCD and how they can help.”
TCD kills a tree within two to three years after initial symptoms are detected and is transmitted by a small twig beetle. TDA plant inspectors and foresters will assess the infestation and to see if more areas need to be quarantined. So far, ten adjacent counties are also restricted for movement of walnut products and hardwood firewood.
TDA officials are asking people to help prevent the spread of TCD by several ways: don’t transport firewood within Tennessee, including firewood for camping trips. Buy the wood from a local source. Don’t bring wood home. Also, don’t buy or move firewood from outside the state and watch for signs of infestation in black walnut trees.
The TCD spread coincides with the discovery of the Emerald Ash Borer, an invasive insect that destroys ash trees, in Claiborne County. While not directly related to TCD, and not yet discovered in Sevier County, the insect can also be spread county to county by transporting firewood.
“People located in surrounding areas to the quarantine can expect next year to see more purple traps as these are an important part of the surveying process,” Haun said. “The traps are coated with an adhesive that captures insects when they land. The color is thought to be attractive to EAB, and is relatively easy for humans to spot among the foliage.”
The TDA Division of Forestry estimates that 1.38 million black walnut trees in Tennessee’s urban areas are potentially at risk from TCD, representing an estimated value loss of $1.37 billion.
Residents are urged to visit www.tn.gov/agriculture for further information or call TDA’s Regulatory Services Division at 1-800-628-2631.
Tree Killing Disease Spreads
By Ben Lawson