Except as provided in subsection (c), no person shall import, enter, export, or move in interstate commerce any plant pest, unless the importation, entry, exportation, or movement is authorized under general or specific permit and is in accordance with such regulations as the Secretary may issue to prevent the introduction of plant pests into the United States or the dissemination of plant pests within the United States.
The Secretary may issue regulations to allow the importation, entry, exportation, or movement in interstate commerce of specified plant pests without further restriction if the Secretary finds that a permit under subsection (a) is not necessary.
Any person may petition the Secretary to add a plant pest to, or remove a plant pest from, the regulations issued by the Secretary under paragraph (1).
Any letter, parcel, box, or other package containing any plant pest, whether sealed as letter-rate postal matter or not, is nonmailable and shall not knowingly be conveyed in the mail or delivered from any post office or by any mail carrier, unless the letter, parcel, box, or other package is mailed in compliance with such regulations as the Secretary may issue to prevent the dissemination of plant pests into the United States or interstate.
Nothing in this subsection authorizes any person to open any mailed letter or other mailed sealed matter except in accordance with the postal laws and regulations.