9.—(1) Article 66A (preservation of trees in conservation areas) shall not apply to -
(a)the cutting down, uprooting, topping or lopping of a tree in the circumstances mentioned in Article 65(3) or in the Third Schedule of the prescribed form of tree preservation order set out in the Schedule;
(b)the cutting down or uprooting –
(i)of a tree whose diameter does not exceed 75 millimetres; or
(ii)where carried out for the sole purpose of improving the growth of other trees, of a tree whose diameter does not exceed 100 millimetres; or
(c)the topping or lopping of a tree whose diameter does not exceed 75 millimetres.
(2) For the purpose of this regulation –
(a)where a tree has more than one stem at a point 1.5 metres above the natural ground level its diameter shall be treated for the purposes of paragraph (1)(b)(i) and (c) or paragraph (1)(b)(ii) as exceeding 75 millimetres or 100 millimetres respectively, if any stem when measured over its bark at that point exceeds 75 millimetres or 100 millimetres respectively;
(b)in any other case, the diameter of a tree shall be ascertained by measurement, over the bark of the tree, at a point 1.5 metres above the natural ground level.