The producers of tree fruit subject to the provisions of this chapter may at any time, by referendum conducted by the department and approved by a majority of the producers voting, establish an additional assessment for programs including but not limited to sanitation programs and the reregistration of plant protection products for use on minor crops. The members of the commission may, subject to approval by two-thirds of the voting members of the commission, suspend all or part of the assessments on tree fruit under this section.