20.—(1) The occupier or other person in charge of premises who knows or suspects that any plant pest to which this article applies is present on the premises or any other person who, in the course of his duties or business, becomes aware of or suspects the presence of such plant pest on any premises, shall immediately give notice to the appropriate Minister or an inspector of the presence or suspected presence of such plant pest.
(2) This article applies to any plant pest—
(a)which is of a description specified in Schedule 6; or
(b)which is not normally present in Great Britain and is likely to be injurious to plants in Great Britain;
but is subject to the exceptions set out in Schedule 6.