RICHMOND, Va. (AP) — State agriculture officials have widened a quarantine area intended to slow the spread of a disease that attacks walnut trees.

The Thousand Cankers Disease quarantine now includes the counties of Fairfax and Prince William and the cities of Fairfax, Falls Church, Manassas and Manassas Park. These are in addition to the counties of Chesterfield, Goochland, Hanover and Henrico, and the cities of Colonial Heights and Richmond. They had already been quarantined.

The Virginia Department of Agriculture and Consumer Services says the quarantine prevents walnut plants, lumber, stumps, firewood and mulch from being moved out of those cities and counties.

The disease is spread by the invasive walnut twig beetle, which introduces a fungus into the tree that eventually kills it. There is no treatment for the disease.

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