Facts
A.- By contract dated 21 May 1980, [H.] leased 374 ares of meadow from J. On 8 September 1987, [J.] terminated the lease for the end of April 1989. On 28 December 1987, he sold these lands, as well as an additional 7.5 hectares of meadows and forests, to a foundation. On 1 March 1988, the new owner also terminated the lease for 31 March 1989.
B.- On 16 December 1987, the tenant requested the Lease Tribunal to extend the lease by six years. The foundation, having substituted [J.], concluded that the request should be rejected. The Lease Tribunal partially granted the request and extended the lease by five years. On appeal by the foundation, the Higher Tribunal extended the lease by four years until 30 April 1993.
C.- The foundation appealed against this decision. It requests the Federal Tribunal to reject the extension request, subsidiarily to remand the case to the previous instance, and, in a more subsidiary manner, to only extend the lease for the minimum legal duration. [H.] concludes that the appeal should be dismissed and, by way of a joint appeal, requests that the lease be extended by five years until 30 April 1994.
Considerations
According to Arts. 15(1) and 27(2)(c) LALA, the new owner can only terminate the lease if they intend to operate the…