(1) In this section -
"farm land" means land in the State wholly or mainly occupied for the purposes of husbandry, other than market garden land within the meaning of section 654;
"occupation", in relation to any land, means having the use of that land.
(2) The occupation by a dealer in cattle, or a dealer in or a seller of milk, of farm land which is insufficient for the keep of the cattle brought on to the land shall be treated as the carrying on of a trade, and the profits or gains thereof shall be charged under Case I of Schedule D.