The Washington apple commission and the Washington state fruit commission shall supply the director with a list of known producers subject to paying assessments to the respective commissions. The director, in addition, shall at the commission's cost compile a list of known tree fruit producers producing fruit not subject to assessments of the Washington apple commission and the Washington state fruit commission but subject to assessments or becoming subject to assessments under the provisions of this chapter. In compiling such list the director shall publish notice to producers of such tree fruit, requiring them to file with the director a report giving the producer's name, mailing address and orchard location. The notice shall be published once a week for four consecutive weeks in weekly or daily newspapers of general circulation in the area or areas where such tree fruit is produced. All producer reports shall be filed with the director within twenty days from the date of last publication of notice or thirty days of mailing notice to producers of such tree fruit, whichever is later. The director shall for the purpose of conducting any referendum affecting tree fruits subject to the provisions of this chapter keep such list up-to-date when conducting such referendum. Every person who becomes a producer after the list is compiled shall file with the director a similar report, giving his or her name, mailing address and orchard location. Such list shall be final and conclusive in conducting referendums and failure to notify a producer shall not be cause for the invalidation of any referendum.