7 U.S.C. § 1610

This chapter shall take effect as follows: As to agricultural seeds, and the importation of vegetable seeds, on the one hundred and eightieth day after August 9, 1939; as to vegetable seeds in interstate commerce, one year after August 9, 1939; and as to sections 1591 to 1593 of this title, on August 9, 1939.