DEPARTMENT OF AGRICULTURE

[Filed April 28, 2026, 10:05 a.m., effective April 28, 2026, 10:05 a.m.]

Effective Date of Rule: Immediately upon filing.

Purpose: This rule-making order amends chapter 16-470 WAC, Quarantine—Agricultural pests, to expand the boundaries of the Japanese beetle internal quarantine in the southeastern corner of Yakima County and the southwestern corner of Benton County. The quarantine prohibits regulated articles located inside the quarantine area from moving outside of it. The quarantine prevents potentially infested host material from being transported to other parts of the state, thereby limiting the spread of Japanese beetle and protecting noninfested areas from infestation.

Additionally, this rule-making order amends:

(1) WAC 16-470-710 by removing the requirement that growing media must be commercially packaged, and adding it to the regulated articles that are already exempt if commercially produced (which includes humus and compost).

(2) WAC 16-470-715 by adding that dip treatments are not permitted. It also updates the URL for accessing a copy of the National Plant Board's U.S. Domestic Japanese Beetle Harmonization Plan.

Citation of Rules Affected by this Order: Amending WAC 16-470-705, 16-470-710, and 16-470-715.

Statutory Authority for Adoption: RCW 17.24.011 and 17.24.041.

Under RCW 34.05.350 the agency for good cause finds that immediate adoption, amendment, or repeal of a rule is necessary for the preservation of the public health, safety, or general welfare, and that observing the time requirements of notice and opportunity to comment upon adoption of a permanent rule would be contrary to the public interest.

Reasons for this Finding: Immediate amendment of the rule is necessary for the general welfare of the public and is necessary to protect the forest, agricultural, horticultural, floricultural, beekeeping, and environmental interests of this state. Japanese beetle (Popillia japonica Newman) is a highly invasive plant pest native to Japan. It has been known to cause severe damage to more than 300 species of ornamental and agricultural plants, including roses, grapes, and hops. Adult beetles damage plants by skeletonizing foliage and feeding on buds, flowers, and fruit. The larvae also damage the roots of plants, such as turf grass. Although this feeding does not always kill the plant, it weakens it and may reduce the plant's overall yield.

In 2025, the department of agriculture (department) caught 68,242 Japanese beetles in the current internal quarantine area. Since 2021, the department has taken extensive measures to reduce the spread of Japanese beetle, with an ultimate goal of eradicating it. These measures include treating residential and public properties with insecticide, trapping, and establishing an internal quarantine. Despite these efforts, by the end of the 2024 trapping season and again in 2025, numerous Japanese beetles (which indicate a reproducing population) were caught outside of the currently established internal quarantine area. Due to this, immediate action is needed to expand the internal Japanese beetle quarantine to reflect the area of infestation more accurately and strengthen the quarantine's protections. Further, the department believes that the additional amendments under WAC 16-470-710 and 16-470-715 will better align exterior and interior quarantine language, as well as clarify requirements around growing media. These amendments are necessary to prevent the beetles' further dissemination within this state and to protect the state's forest, agricultural, horticultural, floricultural, beekeeping, and environmental interests.

If Japanese beetle becomes permanently established throughout the state, it could severely threaten several of Washington's agricultural industries. The threat this pest poses is particularly concerning due to the area in which the detections have occurred. There are a number of farms and nurseries in close proximity to the detection sites, growing plant species known to be targeted by Japanese beetle. Not only do these beetles pose a threat to the plants themselves, but if established they have the potential to impact the availability of export markets for agricultural commodities grown in the area. Expanding the Japanese beetle internal quarantine and other proposed quarantine amendments will help prevent the spread of this invasive pest and protect Washington's agricultural industries, as well as maintain access to national and international markets.

Number of Sections Adopted in Order to Comply with Federal Statute: New 0, Amended 0, Repealed 0; Federal Rules or Standards: New 0, Amended 0, Repealed 0; or Recently Enacted State Statutes: New 0, Amended 0, Repealed 0.

Number of Sections Adopted at the Request of a Nongovernmental Entity: New 0, Amended 0, Repealed 0.

Number of Sections Adopted on the Agency's own Initiative: New 0, Amended 3, Repealed 0.

Number of Sections Adopted in Order to Clarify, Streamline, or Reform Agency Procedures: New 0, Amended 0, Repealed 0.

Number of Sections Adopted using Negotiated Rule Making: New 0, Amended 0, Repealed 0; Pilot Rule Making: New 0, Amended 0, Repealed 0; or Other Alternative Rule Making: New 0, Amended 0, Repealed 0.

Date Adopted: April 27, 2026.

AMENDATORY SECTION(Amending WSR 24-17-053, filed 8/15/24, effective 9/15/24)

WAC 16-470-705Areas under quarantine.

(1) Exterior: The entire states of Alabama, Arkansas, Colorado, Connecticut, Delaware, Georgia, Illinois, Indiana, Iowa, Kansas, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, Missouri, Nebraska, New Hampshire, New Jersey, New York, North Carolina, Ohio, Oklahoma, Pennsylvania, Rhode Island, South Carolina, Tennessee, Texas, Vermont, Virginia, West Virginia, Wisconsin, the District of Columbia, the Provinces of Ontario and Quebec, and any other state, province, parish, or county where infestations of Japanese beetle are detected are declared to be under quarantine for Japanese beetle.

(a) The director may exempt individual counties of the states under quarantine from meeting the conditions in WAC 16-470-715 if the director determines that:

(i) The state has adopted and is enforcing restrictions on the interstate and intrastate movement of regulated articles that are equivalent to or exceed the restrictions placed on the movement of regulated articles as provided in WAC 16-470-715; and

(ii) Annual surveys are conducted in such counties and the results of these surveys are negative for Japanese beetle; and

(iii) One or more neighboring counties are not subject to an unacceptable heavy Japanese beetle infestation.

(b) A plant health official of any state may request exemption of one or more counties under this subsection. The request must be in writing, and it must state the area surveyed, the survey method, personnel conducting the survey, and dates of any previous Japanese beetle infestations in that county.

(2) Interior: Within the state of Washington, those areas where infestations of Japanese beetle exist are declared to be under quarantine. These areas include:

(a) The portion of Yakima and Benton counties designated as follows: Beginning within Yakima County at latitude N46°19'54" and longitude W120°09'12"; thence easterly to latitude ((N46°19'51" and longitude W119°55'24"; thence northerly to latitude N46°20'43" and longitude W119°55'23"; thence easterly to latitude N46°20'42" and longitude W119°52'53"; thence southerly to N46°19'50" and longitude W119°52'53"; thence easterly across the Yakima-Benton County line to latitude N46°19'50"; and longitude W119°51'38" southerly to latitude N46°18'57" and longitude W119°51'39"; thence easterly to latitude N46°18'57" and longitude W119°50'24"; thence southerly to latitude N46°16'21" and longitude W119°50'25"; thence easterly to latitude N46°16'20" and longitude W119°49'10"; thence southerly to latitude N46°15'28" and longitude W119°49'11"; thence easterly to latitude N46°15'28" and longitude W119°47'56"; thence southerly to latitude N46°14'35" and longitude W119°47'56"; thence westerly to latitude N46°14'36" and longitude W119°49'12"; thence southerly to latitude N46°13'44" and longitude W119°49'12"; thence easterly to N46°13'43" and longitude W119°47'57"; thence southerly to latitude N46°12'51" and longitude W119°47'58"; thence westerly to latitude N46°12'52" and longitude W119°50'28"; thence southerly to latitude N46°11'60" and longitude W119°50'29"; thence westerly to latitude N46°12'00" and longitude W119°51'44"; thence southerly to latitude N46°11'08" and longitude W119°51'44"; thence westerly to latitude N46°11'11" and longitude W120°01'55"; thence northerly and easterly along the Yakama Nation Reservation boundary line; thence northerly and turning westerly along the Yakama Nation Reservation boundary to latitude N46°18'42" and longitude W120°07'57"; then northerly to latitude N46°19'02" and longitude W120°07'57"; then westerly to latitude N46°19'02" and longitude W120°08'42"; thence northerly and westerly and turning southerly along the Yakama Nation Reservation boundary to latitude N46°19'02" and longitude W120°09'00"; thence westerly to latitude N46°19'02"))N46°19'52" and longitude W119°58'45"; thence northerly along State Route 241 to latitude N46°20'43" and longitude W119°58'45"; thence easterly along Van Belle Rd to latitude N46°20'48" and longitude W119°54'14"; thence continuing easterly to latitude N46°20'47" and longitude W119°53'03"; thence southerly to latitude N46°20'42" and longitude W119°53'03"; thence easterly to latitude N46°20'42" and longitude W119°52'53"; thence southerly to latitude N46°19'50" and longitude W119°52'53"; thence easterly across the Yakima-Benton County line to latitude N46°19'50" and longitude W119°51'38"; thence southerly to latitude N46°18'57" and longitude W119°51'39"; thence easterly to latitude N46°18'57" and longitude W119°50'24"; thence southerly to latitude N46°18'38" and longitude W119°50'24"; thence easterly along the intersecting irrigation pipeline to latitude N46°18'34" and longitude W119°48'38"; thence southerly along N Missimer Rd to latitude N46°15'30" and longitude W119°48'37"; thence easterly along W McCreadie Rd to latitude N46°15'33" and longitude W119°47'21"; thence southerly along N Gap Rd to latitude N46°13'24" and longitude W119°47'24"; thence easterly along the Interstate 82 Highway corridor to latitude N46°12'54" and longitude W119°44'36"; thence westerly to latitude N46°12'55" and longitude W119°44'28"; thence southerly along the Interstate 82 entrance ramp to latitude N46°12'50" and longitude W119°44'27"; thence westerly to latitude N46°12'46" and longitude W119°44'40"; thence westerly and turning southerly along Frontier Rd and continuing southerly and westerly along State Highway 22 to latitude N46°11'10" and longitude W119°51'44"; thence southerly to latitude N46°11'08" and longitude W119°51'44"; thence westerly to latitude N46°11'11" and longitude W120°01'55"; thence northerly and easterly along the Yakama Nation Reservation boundary line; thence northerly and turning westerly along the Yakama Nation Reservation boundary to latitude N46°19'02" and longitude W120°08'39"; thence westerly along the northern riverbank of the Yakima River to latitude N46°19'16" and longitude W120°09'12"; thence northerly to the point of beginning.

AMENDATORY SECTION(Amending WSR 24-17-053, filed 8/15/24, effective 9/15/24)

WAC 16-470-710Regulated articles.

The following are declared to be hosts or possible carriers of Japanese beetle and are regulated articles under the Japanese beetle quarantine:

(1) The upper eight inches of topsoil containing vegetative material from all properties including, but not limited to, residential, agricultural, and commercial properties (including construction sites);

(2) Humus, growing media, and compost (except when produced commercially), ((growing media (except when commercially packaged),)) and soil samples;

(3) Yard debris, meaning plant material commonly created in the course of maintaining yards and gardens and through horticulture, gardening, landscaping, or similar activities. Yard debris includes, but is not limited to, grass clippings, leaves, branches, brush, weeds, flowers, roots, windfall fruit, and vegetable garden debris;

(4) Plants for planting and propagation, except when dormant and bareroot and free from soil or growing media, including:

(a) All plants with roots;

(b) Plant crowns or roots;

(d) Corms;

(e) Tubers; and

(f) Rhizomes;

(5) Turfgrass (sod);

(6) Hop bines and unshucked corn ears harvested during the Japanese beetle adult flight season (May 15th through October 15th);

(7) Cut flowers for decorative purposes, including those exposed to open air environments during their harvest, transportation, or trade; and

(8) Any other plant, plant part, article, or means of conveyance when it is determined by the director to present a hazard of spreading live Japanese beetle due to either infestation, or exposure to infestation.

AMENDATORY SECTION(Amending WSR 22-17-068, filed 8/15/22, effective 9/15/22)

WAC 16-470-715Conditions governing the movement of regulated articles into Washington state from external quarantine areas.

Regulated articles are prohibited entry into this state from a state or other area under quarantine listed in WAC 16-470-705(1), either directly, indirectly, diverted or reconsigned, except as provided for below.

(1) Prior notification is required. Persons shipping regulated articles as specified in WAC 16-470-710 into this state from areas within the external quarantine must notify the department's plant services program by sending via email to nursery@agr.wa.gov or other method approved by the department, a copy of the applicable phytosanitary certificate as described in subsection (2) of this section for each shipment. The phytosanitary certificate must state the nature and quantity of the shipment, the name of the intended receiver, and the destination. The person to whom the commodities are shipped must hold the shipment until it is inspected and released by the department.

(2) Each shipment of regulated articles must be accompanied by a phytosanitary certificate from the state of origin certifying that the commodity, soil, or means of conveyance is treated with methods and procedures approved and prescribed by the director. Approved methods and procedures include those specified in the National Plant Board U.S. Domestic Japanese Beetle Harmonization Plan Appendix 1. Shipment to Category 1 States, as amended June 20, 2016, with the exception of dip treatments which are not allowed. A copy of this plan can be accessed at ((https://agr.wa.gov/beetles))https://agr.wa.gov/departments/insects-pests-and-weeds/insects/japanese-beetle/quarantine.

(3) Privately owned houseplants grown indoors may be allowed entry into this state if a department official inspects the plants and determines that they are free from Japanese beetle.