Thousand Cankers Disease has just been detected for the first time in Pennsylvania, in nearby Bucks County. 

The PA Department of Agriculture has ordered a quarantine restricting the movement of wood from Bucks County and other states known to have the disease. The quarantine restricts the movement of all walnut material including nursery stock, live cuttings (scionwood), green lumber, firewood, and other walnut material-- living, dead, cut or fallen-- including stumps, roots, branches, mulch and composted or uncomposted chips.

The disease is caused when Walnut Twig Beetles, which carry a fungus, tunnel beneath the bark of walnut trees, causing small cankers to form.  As more beetles attack the tree, the number of cankers increases, slowly starving the tree of nutrients and causing the tree to die within 10 years of initial infestation.  There is no known cure.  Early symptoms of the disease are yellowing of leaves and foliage-thinning of the upper crown of the tree.  As the disease progresses larger limbs are killed, followed by the trunk.

Since many species of wood-boring insects, including the Walnut Twig Beetle and Emerald Ash Borer, can be spread through transport of infested firewood and logs, campers and homeowners are encouraged to use only locally harvested firewood, burn all of it on-site, and not carry it to new locations.

If you suspect you have seen Thousand Cankers Disease or Walnut Twig Beetles, contact your county cooperative extension office: 
Chester County 610-696-3500
Delaware County 610-690-2655
Lancaster County 717-394-6851

For more information, visit http://www.agriculture.state.pa.us