Subject of Possible Rule Making: Chapter 16-752 WAC, Noxious weed seed and plant quarantine. In response to petitions received from the Washington state noxious weed control board and the Washington state department of ecology, the department is considering adding additional species to the noxious weed seed and plant quarantine, which would prohibit their sale and distribution. These species include: Italian arum (Arum italicum), Ravenna grass (Tripidium ravennae), spurge laurel (Daphne laureola), myrtle spurge (Euphorbia myrsinites), annual bugloss (Lycopsis arvensis), yellow flag iris (Iris pseudacorus), hoary alyssum (Berteroa incana), small-flowered jewelweed (Impatiensparviflora), South American spongeplant (Limnobiumlaevigatum), tree-of-heaven (Ailanthus altissima), and poison hemlock (Conium maculatum). The department is also considering adding American spongeplant (Limnobium spongia) to the noxious weed seed and plant quarantine, updating the accepted scientific names of several plants that are currently quarantined and revising the language to increase clarity and readability and to conform with current industry practices or standards.

Reasons Why Rules on this Subject may be Needed and What They Might Accomplish: The intrusion into this state of nonnative, invasive weed species continues to be a concern. The spread of these weeds presents a risk to the economic well-being of the agricultural, forest, horticultural, and floricultural industries, and the environmental quality and natural resources of the state. A number of these noxious weeds are transported and sold within the state of Washington both as nursery plants and as seeds in packets of flower seeds or "wildflower mixes." Subsequent "escape" of these plants has been a documented source of a number of infestations and has resulted in large public and private expenditures by landowners and land managers, weed boards, and weed districts to control. Initiating quarantines forbidding entry or distribution of weed species may be critical for their exclusion or control.

Some of the candidate species being considered for quarantine are also listed in chapter 16-750 WAC, the state noxious weed list, as a Class A or a Class B noxious weed, requiring mandatory control by county weed boards. Other candidate species are listed as Class C. Designation as a Class C noxious weed allows counties to enforce control if it is beneficial to that county (for example to protect crops). Designation as a noxious weed on the state noxious weed list doesn't prohibit its sale, allowing consumers to buy a plant species that's prohibited by their county weed board. Prohibiting the sale of plants designated under the state noxious weed list for mandatory control will support the efforts of county weed boards to control noxious weeds. Weed species being considered for quarantine that are already listed on the state noxious weed list (Class A or B) include: Ravenna grass, spurge laurel, myrtle spurge, annual bugloss, hoary alyssum, small-flowered jewelweed, South American spongeplant, and poison hemlock. Weed species already listed as Class C include: Italian arum, yellow flag iris, and tree-of-heaven.

The addition of tree-of-heaven (Ailanthus altissima) is also being considered to proactively limit the possible spread of Spotted Lantern Fly (SLF) into the state. Ailanthus is the preferred plant species necessary for SLF to complete their mating cycle. Stopping further sale and spread of this species will reduce the ability for SLF to gain a foothold in Washington. The department conducts annual trapping for SLF and surveillance of established Ailanthus populations. This work will be supported and stengthened [strengthened] by excluding Ailanthus from sale.

American spongeplant is not currently listed on the state noxious weed list, however it is still being considered for quarantine because it is often confused with South American spongeplant. There is some literature which combines these two species into one species with two varieties. Neither species is native to Washington state. Quarantining both species will prevent taxonomic confusion which could result in one species being misnamed and sold.

Process for Developing New Rule: Department staff will discuss any proposed amendments with affected stakeholder groups. Affected stakeholders will also have an opportunity to submit written comments on the proposed rules during the public comment period and will be able to present oral testimony at the public hearing.

Interested parties can participate in the decision to adopt the new rule and formulation of the proposed rule before publication by contacting Brad White, Assistant Director, Plant Protection Division, Washington State Department of Agriculture, P.O. Box 42560, Olympia, WA 98504-2560, phone 360-902-1907, fax 360-902-2094, TTY 800-833-6388, email bwhite@agr.wa.gov, website https://agr.wa.gov/services/rulemaking/wac16-752-noxious-weed-seed-plant-quarantine-102418; or Cindy Cooper, Plant Services Program Manager, Plant Protection Division, Washington State Department of Agriculture, P.O. Box 42560, Olympia, WA 98504-2560, phone 360-902-2062, fax 360-902-2094, TTY 800-833-6388, email ccooper@agr.wa.gov, website https://agr.wa.gov/services/rulemaking/wac16-752-noxious-weed-seed-plant-quarantine-102418.