The public hearings which shall be held from time to time for the purpose of determining whether seed of alfalfa or red clover from any foreign country or region is not adapted for general agricultural use in the United States shall be conducted by the Director, or by a presiding officer duly designated by him. Such hearings shall be conducted in an orderly and informal manner in accordance with such procedure as the presiding officer shall announce at the opening of each hearing. The Administrator of the Agricultural Marketing Service shall, within a reasonable time after the close of the public hearing, make and publish his determination as to whether the said seed is adapted for general agricultural use in the United States. Publication of the determination shall be made in the Federal Register, and through such other media as the said Administrator may deem appropriate.