Walnut Tree Quarantine in Jefferson County Due to Thousand Cankers Disease

NASHVILLE – The Tennessee Department of Agriculture today announced the discovery of a walnut tree killing disease, Thousand Cankers Disease (TCD), in Jefferson County. The county is now under quarantine. Hamblen County is now considered a buffer regulated county because it is adjacent to a quarantined county.  Rhea County is also being placed in the buffer regulated category because Walnut Twig Beetles have been caught in the county but no TCD fungus has been found.

“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 is a progressive disease that may kill a tree within two to three years after initial symptoms are detected. The disease-causing fungus, Geosmithia morbida, is transmitted by the Walnut Twig Beetle, Pityophthorus juglandis. Branches and trunk tissue are killed by multiple infections of the fungus as the beetles carry the fungus from one area to the next.

TDA plant inspectors and foresters will continue to conduct a thorough survey of trees in these areas to assess the extent of the infestation and to see if more areas need to be quarantined. Counties already under quarantine for TCD include Anderson, Blount, Knox, Loudon, Sevier and Union. Adjacent counties to the quarantined areas are also restricted for movement of walnut products and hardwood firewood.

The Tennessee Department of Agriculture Division of Forestry estimates that 1.38 million black walnut trees in Tennessee’s urban areas are potentially at risk from TCD. The risk represents an estimated value loss of $1.37 billion. There are an estimated 26 million black walnut trees on Tennessee public and private timberland potentially valued as high as $1.47 billion.

TDA officials urge area residents and visitors to help prevent the spread of TCD:

• Don’t transport firewood, even within Tennessee. Don’t bring firewood along for camping trips. Buy the wood you need from a local source. Don’t bring wood home with you.

• Don’t buy or move firewood from outside the state. If someone comes to your door selling firewood, ask them about the source, and don’t buy wood from outside the state. 

• Watch for signs of infestation in your black walnut trees. If you suspect your black walnut tree could be infested with TCD, visit www.TN.gov/agriculture/tcd for an online symptoms checklist and report form or call TDA’s Regulatory Services Division at 1-800-628-2631. 

More information about Thousand Cankers Disease and forest health threats in Tennessee can be found at www.ProtectTNForests.org. For more information about other programs and services of the Tennessee Department of Agriculture visit www.tn.gov/agriculture .