State Puts Quarantine on Walnut Materials

Plants, trees, wood, bark and other materials restricted to help state prevent infestation by beetle that causes cankers.

A new state quarantine requires people or businesses that handle of move walnut plants, trees, wood or other material from walnut trees to register with the Kansas Department of Agriculture.

The quarantine is aimed at protecting the state’s black walnut trees from the walnut twig beetle, a dangerous pest that is causing widespread disease in walnut forests in California, Colorado, Idaho, New Mexico, Oregon, Utah and Washington.

The quarantine also identifies products of interest that could provide a vehicle for the walnut twig beetle to arrive in the state.  These include plants, logs, lumber, firewood, bark, mulch, burls, stumps and packing material.

Products brought into the state from known infected areas or uninspected areas must have a certificate that they have been inspected and found free of disease. In areas that conduct regular inspections and are known to be disease and beetle free, the certificate is not required.

Exempt from the quarantine are nuts, nut meat, hulls, finished wood products without bark, and processed lumber without bark that has been heat treated to 133 degrees Fahrenheit and originates from states, territories and foreign countries where the disease and the beetle have not been detected.

Anyone who violates the quarantine is subject to criminal prosecution and could be ordered to pay civil penalties and all expenses associated with treating, destroying or removing regulated articles from the state.

The walnut twig beetle is a minute, yellowish-brown bark beetle native to North America that has strayed from its native host, the Arizona walnut, to black walnut, the walnut tree most common in Kansas. 

When it tunnels its way under the tree’s bark, it can introduce a new form of Geosmithia, a fungus that causes cankers that ultimately kill the tree.  Currently there are no effective methods for controlling the pest or preventing the disease.

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