(1) The registered proprietor of land may lease it for any term exceeding 3 years by a memorandum of lease in an approved form.(2) A lease for a term of 3 years or less is not registrable under this Act.(3) A lease of mortgaged or encumbered land shall not be valid and binding against the mortgagee or encumbrancee unless the mortgagee or encumbrancee has consented in writing to the lease prior to the registration of the lease.