During all times when outdoor labor is practicable, inmates of penal institutions required to labor shall be employed, so far as is possible, in the reclamation of waste places and in cultivating lands for raising produce to be used in public institutions, and in the reforestation, maintenance or development of state forests. Prisoners so employed shall be at all times in the custody and under the direction of the prison officers.
Mass. Gen. Laws ch. 127, § 83