Thousand Cankers Disease has been detected in the counties of Fairfax and Prince William, Va., prompting the Virginia Department of Agriculture and Consumer Services to expand its current TCD quarantine to include those counties and the cities of Fairfax, Falls Church, Manassas and Manassas Park.
In summation, the quarantine area now includes Chesterfield, Fairfax, Goochland, Hanover, Henrico and Prince William counties and the cities of Colonial Heights, Fairfax, Falls Church, Manassas, Manassas Park and Richmond.
VDACS points out that TCD is a disease complex that attacks walnut trees. A fungus Geosmithia morbida is established on the tree by the walnut twig beetle when it tunnels beneath the bark causing an infection that expresses itself in small cankers under the bark of the tree. As more beetles attack the tree, the number of cankers become too much for the tree to bear; the cankers coalesce to girdle twigs and branches, and that restricts the movement of nutrients to the tree, eventually killing it. Thinning or dead branches occur initially at the top of the tree, which will die from the top down.
Trees may be infested for many years before showing symptoms.
VDACS notes that neither the beetle nor the fungus is native to the eastern U.S. There is currently no preventive or curative treatment for the disease.
VDACS says that once TCD is established, it has the potential to spread to uninfested areas, either through natural means or through the artificial movement of infested articles.
The quarantine is designed to prevent the artificial spread of the disease. The quarantine prevents all walnut plants and plant parts of walnut, including green lumber, logs, stumps, firewood, roots, branches, mulch and chips, are prohibited from being moved out of the quarantine area.
More information on Thousand Cankers Disease in the Eastern U.S. is available at www.fs.fed.us/foresthealth/fhm/sp/tcd/tcd.shtml.