The common barberry, (Berberis vulgaris) and many of its horticultural varieties as well as certain other species of Berberis, Mahonia, and Mahoberberis are the alternate host plants of the disease black stem rust, caused by the organism Puccinia graminis. Black stem rust attacks wheat, oats, barley, rye, and many other cultivated and wild grasses, often resulting in material financial loss to growers of these crops in Washington. Without access to alternate host plants, Puccinia graminis cannot reproduce, and black stem rust is eliminated or greatly decreased. The director of agriculture, under authority granted by chapters 17.24, 15.13 and 15.08 RCW, has determined that the regulation and exclusion of rust susceptible varieties of barberry and related Berberis, Mahonia, and Mahoberberis species is necessary to protect agricultural crops of the state of Washington.

(1) Persons owning or controlling public or private lands in Adams, Asotin, Benton, Chelan, Columbia, Douglas, Ferry, Franklin, Garfield, Grant, Kittitas, Klickitat, Lincoln, Okanogan, Pend Oreille, Spokane, Stevens, Walla Walla, Whitman, or Yakima counties are required to destroy all rust-susceptible barberry bushes and to keep the land free from such plants.

(2) No person who is or should be licensed as a nursery dealer under provisions of chapter 15.13 RCW may sell, offer for sale, ship or grow any rust susceptible variety of barberry or related Berberis, Mahonia, and Mahoberberis species, as defined in 7 C.F.R. 301.38-2.

No restrictions are placed by this rule on the growing or intrastate movement of rust-resistant Berberis, Mahonia, and Mahoberberis plants, plant parts or seeds, as defined in United States Department of Agriculture Animal and Plant Health Inspection Service regulations in 7 C.F.R. 301.38-2.

This rule does not apply to cuttings (without roots) of Mahonia shipped for decorative purposes and not for propagation.

(1) All intrastate and interstate shipments and/or individual packages of Berberis, Mahonia or Mahoberberis plants, seeds, or parts capable of propagation must be plainly labelled or stamped on the outside of the package with botanical species or horticultural variety and the name and address of the consignee and consignor. In addition, when required by federal regulations in 7 C.F.R. 301.38, each shipment and/or individual package containing Berberis, Mahonia or Mahoberberis plants or seeds must have securely attached to the outside, a valid shipping permit issued by the United States Department of Agriculture authorizing its interstate movement.

(2) Any Berberis, Mahonia and Mahoberberis plants, plant parts or seeds that are in violation of this barberry and black stem rust quarantine are subject to destruction, shipment out-of-state or other disposition in a manner prescribed by the department. Any such action will be at the expense of the owner or owner's agent and without compensation.