The purpose of the regulations in this part is to prevent the dissemination of plant pests into the United States, or interstate, by regulating the movement of plant pests into or through the United States, or interstate, and the movement of means of conveyance, earth, stone and quarry products, garbage, and certain other products and articles into or through the United States, or from any Territory or possession into or through any other Territory or possession or the continental United States. The Deputy Administrator shall employ procedures to carry out this purpose which will impose a minimum of impediment to foreign commerce and travel whenever practicable, consistent with proper precaution against plant pest dissemination. The same policy is to be applied in the case of interstate commerce and travel.