When seed or screenings have been refused admission into the United States under the Act or the joint regulations promulgated thereunder, the owner or consignee of such seed or screenings may submit a request to the Director for a hearing in which he may show cause, if any he have, why such seed or screenings should be admitted. Request for such hearing shall be embodied in a writing signed by the owner or consignee or by his attorney or agent. The Director shall thereupon fix, and notify the owner or consignee of, the time when and place at which the hearing will be held. The hearing shall be conducted in an orderly and informal manner by the Director or by a presiding officer duly designated by him, and it shall be governed by such rules of procedure as the presiding officer shall announce at the opening of the hearing. The determination as to whether the seed or screenings may be admitted into the United States shall be made by the Administrator of the Agricultural Marketing Service, within a reasonable time after the close of the hearing, and the owner or consignee of the seed or screenings who requested the hearing and the Secretary of the Treasury shall be duly notified as to such determination.