Section 3(D) in Tamil Nadu Urban Land (Ceiling and Regulation) Act, 1978
(D)where on the commencement of this Act, any land is actually used mainly for the purpose of agriculture, but is used mainly for a purpose other than agriculture, after such commencement, then on and from the date on which such land is used for any purpose other than agriculture, the land shall be deemed to be vacant land and accordingly the provisions of this Act shall apply.
