The provisions of sections 266.051, 266.061 and 266.071 shall not apply:

(1) To seed or grain not intended for seeding purposes;

(2) To seed in storage, or being transported or consigned to an establishment for cleaning or processing; provided, that the invoice or labeling accompanying any shipment of said seed bears the statement “seed for processing”; and provided that any labeling or other representation which may be made with respect to the uncleaned or unprocessed seed shall be subject to this law;

(3) To any carrier in respect to any seed transported or delivered for transportation in the ordinary course of its business as a carrier; provided, that such carrier is not engaged in producing, processing, or marketing agricultural or vegetable seed subject to the provisions of this law;

(4) To a farmer who sells unlabeled seed of his own production;

(5) To seed for use in experimental or breeding purposes, when approved by the director of agriculture on a form established by regulation.