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The Thousand Cankers Disease (TCD) has been discovered in Tennessee. This discovery by the Tennessee Department of Agriculture comes just after the Emerald Ash Borer was found in East Tennessee. Thousand Cankers Disease is a fungus, Geosmithia, transmitted by a small twig beetle and affects Black Walnut trees.
According to a news release by the TN.gov Newsroom, "TCD is a progressive disease that kills a tree within two to three years after initial infection." "Branches and trunk tissue are killed by repeated infections by the fungus, as the beetles carry the fungus into new bark."
The US Department of Agriculture Forest Service describes the three symptoms of the disease as "branch mortality, numerous small cankers on branches and the bole, and evidence of tiny bark beetles. The earliest symptom is yellowing foliage that progresses rapidly to brown wilted foliage, then finally branch mortality. The fungus causes distinctive circular to oblong cankers in the phloem under the bark, which eventually kill the cambium. The bark surface may have no symptoms, or a dark amber stain or cracking of the bark may occur directly above a canker. Numerous tiny bark beetle entrance and exit holes are visible on dead and dying branches, and bark beetle galleries are often found within the cankers. In the final stages of disease, even the main stem has beetle attacks and cankers."
Officials with the Tennessee Department of Agriculture are urging residents and visitors to help curb the spread of this disease by not transporting firewood - even within Tennessee, by not buying or moving firewood from outside the state, and to watch for signs of infestation in black walnut trees.
Read more about the Thousand Cankers Disease at the TN.gov Newsroom or the Tennessee Department of Agriculture web sites.
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