"Certification" means that the lot of seed potatoes was inspected and meets the requirements of this chapter.

"Cull" means any lot of potatoes rejected for certification for any reason.

"Department" means the department of agriculture of the state of Washington.

"Director" means the director of the department of agriculture or their duly appointed representative.

"Disease tested" means tested for and found free of all of the following diseases: Potato virus A (PVA), potato virus M (PVM), potato virus S (PVS), potato virus X (PVX), potato virus Y (PVY), potato leafroll virus (PLRV), potato mop top virus (PMTV), potato spindle tuber viroid (spindle tuber), Erwinia carotovora ssp. carotovora (soft rot), Erwinia carotovora ssp. atroseptica (black leg) and Clavibacter michiganense spp. sepedonicus (ring rot).

"ELISA testing" means laboratory testing by enzyme-linked immunosorbant assay or other equivalent methodologies.

"Micropropagated" means potato stock propagated using aseptic laboratory techniques and culture media to promote plant tissue growth.

"Microtubers" means tubers produced in vitro by a micropropagated plant or plantlet.

"Minitubers" means tubers produced under controlled greenhouse conditions.

"Nematode" means plant parasitic nematodes capable of infesting potatoes, including but not limited to the genus Meloidogyne.

"Nuclear stock" means plantlets, microtubers, minitubers, or seed potatoes produced from prenuclear stock, and grown in the field for the first time.

"Plot" means a seed potato planting that is 0.25 acre or less in size.

"Powdery scab" means the disease caused by the fungus Spongospora subterranea.

"Prenuclear" means micropropagated plants or tubers and plants or minitubers produced in a greenhouse.

"Quarantine pest" means a pest of potential economic importance and not yet present in the state, or present but not widely distributed and being officially controlled.

"Recertification" means the process of certifying a seed lot that was certified the previous year.

"Rogue" means removing diseased or undesirable plants, including all associated plant parts, from a seed potato field.

"Seed lot" means a field, in whole or in part, or a group of fields producing seed potatoes, or the potato tubers harvested from a seed potato field.

"Seed potato farm" means a separate seed potato enterprise, including all land, equipment, storages and all facilities used to produce only certified seed potatoes.

"Seed potatoes" means vegetatively propagated tubers used for potato production.

"Seed source" means seed potatoes produced by an individual seed potato farm within a particular seed production area.

"Trace" means a barely perceivable indication of plant disease that amounts to less than 0.001 percent of sample.

"Tolerance" means the maximum acceptable percentage of potato plants or tubers that is diseased, infected by plant pests, defective or off-type based on visual inspection or laboratory testing by the director or other authorized person.

"Unit method" means a method of planting in which cut seed pieces from one tuber are dropped consecutively in a row, or in which all tubers from one plant are dropped consecutively in a row.

(1) Participation in this program is voluntary, except as provided in chapter 15.15 RCW, and may be withdrawn at the option of the applicant.

(2) The department will refuse or cancel certification of any seed potato planting or seed potato lot that fails to comply with this chapter.

(3) Issuance of a certified state of Washington tag, stamp or other document under this chapter means only that the tagged, stamped or otherwise documented seed potatoes have been subjected to procedures and requirements described in this chapter and determined to be in compliance with its standards and requirements. The department disclaims all express or implied warranties, including without limitation implied warranties of merchantability and fitness for particular purpose, regarding all plants, plant parts, and plant materials under this chapter. Certification is based solely on compliance with this chapter.

(4) The department is not responsible for disease, genetic disorders, off-type, failure of performance, mislabeling or otherwise, in connection with this chapter. No grower, dealer, government official, or other person is authorized to give any expressed or implied warranty, or to accept financial responsibility on behalf of the department regarding this chapter.

(1) To apply for certification, applicants must use the form provided by the department and furnish all information requested, including the date, name, signature and address of the applicant, lot number, seed source identification number, variety, class planted, acres, date planted, seed spacing at planting, average length of rows, year the field was last cropped to potatoes, along with their variety and lot number, and a map of the field location. Applications for certification must reach the department on or before June 15 of each year, accompanied by the appropriate fee, field location maps and evidence of eligibility such as tags or certificates. A North American Certified Seed Potato Health Certificate is required for evidence of eligibility for seed lots originating in other states or Canada, and must be submitted with the application. A certificate of compliance is required for evidence of eligibility and must be submitted with the application for seed lots originating in Washington state except when planted back on the same seed potato farm. Unless prior approval has been granted, late applications will be assessed a late fee of twenty dollars per application. The department will not accept applications after July 10.

(2) Separate applications are required for each variety, seed source, and seed lot except as described in subsection (5) of this section.

(3) Separate applications are required for each field location that is separated by more than one hundred feet.

(4) Growers may withdraw a seed potato lot from certification for any reason by notifying the department in writing.

(5) Growers may use a single application for multiple varieties planted in a field plot totaling 1/8 acre or less. The application must contain the information required in subsection (1) of this section for each variety. Growers shall use one identification number for the field plot with a separate letter designation for each variety in the field plot.

(1) The seed potato certification fee is twenty-nine dollars per acre or fraction of an acre.

(2) The certification fee for a field plot is twenty dollars per application.

(3) The department may assess additional fees for time and mileage pursuant to chapter 16-470 WAC.

(4) Growers must submit a minimum of fifty percent of the total certification fees with the applications.

(5) Final payment of certification fees is due and payable November 1 of each year.

(6) For the purpose of fee assessment, acreage may be adjusted by no more than ten percent prior to the first field inspection. The department will refund certification fees, if a written withdrawal notice is received by the department prior to the first field inspection.

(7) Growers are not required to pay the final half of the certification fee on lots rejected or withdrawn before the second inspection.

(8) The department will deny certification to any applicant who fails to pay fees when due.

(9) The department will not accept applications from any grower owing the department for previous fees.

(1) All seed potatoes entered for certification are classified on the basis of production phases as follows:

(a) Prenuclear (PN) - Micropropagated potatoes or seed potatoes grown in a greenhouse or screenhouse under sanitary conditions free of insects, weeds that can harbor potato diseases or other sources of disease contamination.

(b) Nuclear (N) - First field production year.

(c) Generation 1 (G1) - Second field production year.

(d) Generation 2 (G2) - Third field production year.

(e) Generation 3 (G3) - Fourth field production year.

(f) Generation 4 (G4) - Fifth field production year.

(g) Generation 5 (G5) - Sixth field production year.

(2) If a seed lot fails to meet the standards established in this chapter for its class, then it will be reclassified to the earliest generation for which it meets established standards.

(1) A grower may not recertify any seed lots, except nuclear, if ring rot has been detected on their seed potato farm during the previous two years. Nuclear seed potatoes may be recertified by the original grower if laboratory testing of the seed by a laboratory approved by the department shows negative results for ring rot.

(2) Prenuclear class.

(a) Prenuclear seed lots must be derived from disease tested micropropagated plants. All testing methods and laboratories must be approved by the department.

(b) A minimum of one percent (and not less than 20 samples) of prenuclear seed produced in a greenhouse must be tested and found free of potato virus X (PVX), potato virus Y (PVY), potato virus S (PVS), potato leafroll virus (PLRV), Erwinia carotovora ssp. caratovora (soft rot), Erwinia carotovora ssp. atroseptica (black leg), and Clavibacter michiganense ssp. sepedonicus (ring rot).

(c) The department will inspect all facilities used in the production of prenuclear class seed potatoes on a periodic basis. Department approval is necessary in order to utilize these facilities.

(3) Nuclear class.

(a) Nuclear class seed potatoes must be propagated entirely from prenuclear plants.

(b) Each nuclear class seed lot must be distinctly separated in storage and in the field.

(c) If a ground rig is used for spraying, wide enough spacing between rows must be left, so that tires will not touch plants during the growing season.

(d) Growers must plant cut seed and single drop seed separately, with single drop seed identified.

(4) Generations 1, 2, 3, 4 and 5.

(a) Growers must leave a distinct separation between lots of seed potatoes from different classes. The same separation must be left between different varieties, unless the varieties are readily distinguishable by visual observation. The separation must consist of one of the following:

(i) A strip of land at least six feet in width, that is unplanted or planted with another crop; or

(ii) Visible markers such as flags in every corner of the lot, and also at intervals not to exceed 100 yards.

(b) When more than one lot of seed potatoes is planted in the same field, growers must stake or mark the identity of each lot.

(1) Only seed potatoes derived from plants that have been disease tested and certified by an official certification agency are eligible for certification.

(2) Only seed lots that meet or exceed the minimum requirements as established in this chapter are eligible for certification. A seed lot that has more than a trace amount of virus disease noted during any field inspection is not eligible for recertification, unless it has been postharvest tested and meets the minimum standards established in WAC 16-324-420.

(3) A postharvest test is required for seed lots that will be recertified, except when planted back on the same seed potato farm.

(4) In order to be eligible for certification in Washington state, seed lots from other states or countries must be eligible for recertification in the state or country of origin and must meet the requirements of this chapter.

(5) A seed lot blended from two or more different sources of seed is not eligible for recertification.

(6) A seed lot infected with powdery scab is not eligible for recertification.

(7) Generation 5 (G5) seed lots are not eligible for recertification.

(8) The director may grant written permission to allow seed potato lots that fail to meet the eligibility requirements to be planted for recertification. Such written permission shall specify the conditions under which planting is allowed. Prior to granting permission, the director shall consult with the Washington state seed potato commission.

(1) All field locations for nuclear and generation 1 production must have prior approval from the department.

(2) Generation 2 through generation 5 must be isolated by at least three hundred fifty feet from all noncertified potatoes.

(3) When ring rot is found in a field planted with more than one lot of seed potatoes, the department will reject the entire field.

(1) The department will not accept any field infested with nematodes.

(2) Detection of ring rot in a field will make that field ineligible for production of certified seed potatoes for three years. Presence of volunteer potato plants in a field with ring rot history will disqualify the current field crop for certification. Plants outside of the defined row are considered volunteers.

(3) Nuclear class seed potatoes must be produced in a field that has not been planted with potatoes for at least four years.

(4) Generation 1, 2, 3, 4, and 5 class seed potatoes must be produced in a field that has not been planted with potatoes during the previous year unless the prior potato crop was certified seed potatoes of an earlier class of the same variety. Volunteer plants from a previously planted seed potato crop will cause the class designation of the current crop to be changed to the appropriate generation of the volunteer plants.

(1) Chemicals used in the sanitation of equipment should be those recommended by the Pacific Northwest Plant Disease Management Handbook. This handbook is available online at:http://pnwhandbooks.org/plantdisease/. Vector control must be maintained throughout the growing season as recommended by the Pacific Northwest Insect Management Handbook. This handbook is available online at: http://pnwpest.org/pnw/insects/.

(2) Seed stocks entered for certification should be planted and harvested prior to handling any other seed stock. The earliest generation should be handled prior to later generations within the program.

(3) Only department-approved containers shall be used during the digging, storage, and packing process.

(1) Compliance with a 0.0% tolerance is not intended, nor should it be construed, to mean that the lot inspected is free from the disease. It means that the disease was not detected during visual inspections of the seed lot.

(2) First and second field inspection tolerances, expressed as percentages.

*Tolerance for black leg does not apply to G5.

(1) The department will visually inspect each seed lot at least two times during the growing season. The department may make additional inspections if the department deems it necessary.

(2) The department will reject all seed lots that do not comply with minimum field inspection standards at the time of inspection.

(3) Growers must notify the department of unusual field conditions, which may cause premature dying from any cause prior to the final reading of the field.

(4) Postharvest testing is required for any seed lot with a field condition preventing adequate field evaluation at the time of the first field inspection.

(5) If the department is unable to perform the final field inspection of a seed potato lot for any reason at least one of the following actions will be taken:

(a) The seed lot will be denied certification;

(b) The seed lot will be denied recertification; and/or

(c) The lot must be postharvest tested and found free of ring rot.

(6) The department will reject any seed lot in which ring rot is detected and will conduct additional inspections on all of the grower's remaining seed lots. The department will not recertify any seed lot associated with or planted after the rejected lot. The department will submit samples of ring rot detected during field inspections to an approved laboratory for confirmation.

(7) The department may require a postharvest test and withhold certification pending results of the postharvest test on seed potato lots exposed to any chemical that causes tuber-borne injury. Any seed potato lot showing five percent or greater tuber-borne chemical damage in the postharvest test will be rejected for certification.

(1) Postharvest testing is required for the following lots:

(a) All Generation 1 lots except lots that are less than 0.25 acre and planted back on the same seed potato farm;

(b) Seed lots sold for recertification; and

(c) Lots for which a postharvest test is required by WAC 16-324-399.

(2) Testing of seed lots submitted for postharvest testing in subsection (1)(a) and (b) of this section by ELISA for PVY is optional. Seed lots officially sampled by the department for PVY testing will be subject to disease tolerance listed under WAC 16-324-420.

(3) A minimum of four hundred tubers must be submitted for each seed lot entered for postharvest testing. Seed lots less than 0.25 acre in size must submit a minimum of four tubers per total hundred weight with a minimum of fifty tubers.

(4) The applicant is responsible for the cost of postharvest testing.

(5) Seed lots in the postharvest test which fail to comply with the disease tolerance requirements set forth in WAC 16-324-420 are not eligible for recertification.

(a) The applicant must notify in writing all receivers of any seed lot that failed to comply with postharvest tolerances set forth in WAC 16-324-420.

(b) Acceptance of a seed lot that fails to comply with the tolerances set forth in WAC 16-324-420 must be based on a written buyer/seller agreement. The grower must provide the department with a copy of the written agreement within thirty days of receiving the postharvest results.

(1) Each seed lot must be stored with its identity maintained. All tubers from a unit planting method must be numbered and stored as an identifiable unit for the next year's planting.

(2) Each storage or room containing more than one seed lot must have an impermeable barrier between each lot.

(a) The department will reject any seed lot in which ring rot or nematode is found.

(b) Noncertified potatoes must not be stored in the same facility as certified seed potatoes.

(3) The applicant must notify in writing receivers of any seed lot found to be infected with ring rot. The applicant must provide the department with a copy of this notification when it is sent to the receiver.

(4) All seed classes must be graded according to the United States Standards for Grades of Seed Potatoes.

(5) Each container or sack must be identified with an official Washington seed potato tag listing the grower's name, address, seed lot number, net weight, variety and classification unless such information is printed on the sacks or containers.

(6) The department issues tags to the grower. The grower is required to comply with all of the following:

(a) Tag the sack or container as the potatoes are sorted;

(b) Allow inspection of graded seed potatoes at any time;

(c) Remove the tags from out-of-grade potatoes under the supervision of the department; and

(d) Return all unused tags to the department.

(7) The department may issue a compliance agreement authorizing the grower to tag seed potatoes.

(8) Bulk shipments must be identified with the information required in subsection (5) of this section.

(1) Grading of seed potatoes is the responsibility of the grower. The department monitors grading activities for compliance with the United States Standards for Seed Potatoes and established state standards for seed potatoes.

(2) Upon request, the department provides shipping point inspections for seed potatoes. Fees established in chapter 16-470 WAC apply to all shipping point inspections.

(3) Three colors of tags are authorized for use on certified seed potatoes.

(a) Blue tags are used for seed potatoes which meet or exceed minimum requirements of United States Standards for US Number 1 grade of seed potatoes.

(b) Yellow tags indicate a contract grade between buyer and seller.

(c) White tags are used for seed potatoes which meet or exceed minimum requirements of US Number 1 standards for grade of seed potatoes except, that the size may not be less than one ounce or more than three ounces in weight.