Where notice to terminate the tenancy of an agricultural holding is given, either by the tenant or by the landlord, the tenant shall not, subject to any agreement to the contrary, at any time after the date of the notice, sell or remove from the holding any manure or compost, or any hay or straw or roots grown in the last year of the tenancy, unless and until he has given the landlord or the incoming tenant a reasonable opportunity of agreeing to purchase on the termination of the tenancy at their fair market value, or at such other value as is provided by the lease, the said manure, compost, hay, straw or roots.