RCW 15.08.250

Whenever the director determines that a particular pest cannot be eradicated or effectively controlled by ordinary means, or that it is impractical to eradicate or control it without the destruction in whole or in part of uninfected host plants, he or she may issue a proclamation setting out the host-free period or host-free district, or both, describing the host plant and the district wherein planting, growing, cultivating, or maintenance in any manner of any plants or products capable of continuing the particular pests is prohibited during a specified period of time and until the menace therefrom no longer exists.