15. The appropriate UK plant health authority need not demarcate an area in relation to a finding of the plant pest in a relevant UK territory where—
(a)there is evidence that—
(i)the infestation has been caused by the movement of susceptible plants to the area of infestation and those plants were infested with the plant pest prior to their movement to that area; or
(ii)it is an isolated finding which is not expected to lead to the establishment of the plant pest; and
(b)it has ascertained that the plant pest is not established in the area and will not successfully breed or spread if appropriate eradication measures are taken.
16. Where the appropriate UK plant health authority does not demarcate an area for the reasons specified in paragraph 15(a) and (b), the appropriate UK plant health authority must ensure that—
(a)measures are immediately taken for the purpose of promptly eradicating the plant pest and preventing its spread;
(b)over the relevant period, monitoring is carried out within one km of the infested plants or the place at which the plant pest was found, which must be regular and intensive in the first year;
(c)the infested plants are destroyed;
(d)tracing back to the origin of the infestation and tracing of plants associated with the infestation is carried out as far as possible, along with examinations of the plants traced for any sign that they are infested with the plant pest, which must include targeted destructive sampling;
(e)activities to raise public awareness of the threat posed by the plant pest are carried out;
(f)any other measure which may contribute to the eradication of the plant pest is taken, taking account of the guidelines in ISPM No. 9 and ISPM No. 14.