Diseased black walnut tree in Bucks prompts quarantine

An incurable disease found in a black walnut tree in Plumstead Township, Bucks County, has prompted measures to safeguard the state's $25 billion hardwoods industry.

Thousand-cankers disease, the result of tunneling by fungus-carrying walnut twig beetles, causes trees to slowly starve. Since the beetles are the size of a poppy seed, they are tough to detect.

Under a quarantine declared Friday by the state, no hardwood firewood, or walnut materials, living or dead, can leave the county except for nuts, processed lumber, and finished wood products without bark. Mulch and wood chips, composted and uncomposted, are included in the ban.

The quarantine also seeks to stop shipments into Pennsylvania of walnut materials and hardwood firewood from states with cases of the disease, including Virginia, Arizona, California, Colorado, Idaho, Nevada, New Mexico, Oregon, Tennessee, Utah, and Washington.

"To help ensure this disease does not spread to other regions throughout the state, I urge Pennsylvanians to comply with the quarantine restricting the movement of wood from Bucks County," said state Agriculture Secretary George Greig.

Violators risk criminal penalties of up to 90 days in jail and a $300 fine for each infraction, or civil penalties of up to $20,000 per offense, according to the state.

Since first detected in 2003 in Colorado in 2003, thousand-cankers disease has killed black walnut trees in many Western states. Other types of walnuts may also be susceptible.

Using only local firewood can help cut the spread of a variety of wood-boring insects, the department advised.

The tree's owner in Plumstead Township reported the case to the Penn State Cooperative Extension. Symptoms begin with yellowing leaves and loss of upper leaves, followed by dying limbs, and finally a dying trunk.

To report suspicions about agricultural pests, contact the local county cooperative-extension office, or call the Agriculture Department's toll-free pest hotline at 1-866-253-7189.