(a) An inspector may declare any airport within a quarantined State to be a regulated airport when he or she determines that adult populations of Japanese beetle exist during daylight hours at the airport to the degree that aircraft constitute a threat to spread the Japanese beetle and aircraft destined for the States listed in § 301.48(b) may be leaving the airport.

(b) An inspector shall terminate the designation provided for under paragraph (a) of this section when he or she determines that adult populations of Japanese beetle no longer exist at the airport to the degree that the aircraft pose a threat to spread the Japanese beetle.