(a) Except as otherwise provided in paragraph (b) of this section, the Administrator will list as a quarantined area in paragraph (c) of this section, each State or each portion of a State in which the Asian longhorned beetle has been found by an inspector, in which the Administrator has reason to believe that the Asian longhorned beetle is present, or that the Administrator considers necessary to regulate because of its inseparability for quarantine enforcement purposes from localities where Asian longhorned beetle has been found. Less than an entire State will be designated as a quarantined area only if the Administrator determines that: