Mass. Gen. Laws ch. 61B § 1
Land not less than five acres in area shall be deemed to be recreational land if it is retained in substantially a natural, wild, or open condition or in a landscaped or pasture condition or in a managed forest condition under a certified forest management plan approved by and subject to procedures established by the state forester in such a manner as to allow to a significant extent the preservation of wildlife and other natural resources, including but not limited to, ground or surface water resources, clean air, vegetation, rare or endangered species, geologic features, high quality soils, and scenic resources. Land not less than five acres in area shall also be deemed to be recreational land which is devoted primarily to recreational use and which does not materially interfere with the environmental benefits which are derived from said land, and is available to the general public or to members of a non-profit organization including a corporation organized under chapter one hundred and eighty.
For the purpose of this chapter, the term recreational use shall be limited to the following: hiking, camping, nature study and observation, boating, golfing, non-commercial youth soccer, horseback riding, hunting, fishing, skiing, swimming, picnicking, private non-commercial flying, including hang gliding, archery, target shooting and commercial horseback riding and equine boarding.
Such recreational use shall not include horse racing, dog racing, or any sport normally undertaken in a stadium, gymnasium or similar structure.
Mass. Gen. Laws ch. 61B, § 1