The intrusion of nonnative, invasive plant pest species into Washington state is a significant public concern. Plant pest species include insects, nematodes, snails, plant diseases, weeds and other species which harm plants or plant products. If established, such plant pests have potential to cause harm to the state's forest, agricultural, horticultural, floricultural and apiary industries, to damage natural resources and the property of private landowners, to reduce environmental quality, and to threaten the diversity and abundance of native species. In recent years, many of these invasive plant pests have entered the state, in some cases causing significant private and public expense for monitoring, control or eradication. This rule is intended to aid in the exclusion, tracking, identification, control and/or eradication of invasive plant pests which may enter the state on or in association with horticultural plants, in order to protect public health, safety, welfare, and the environment.