Martinsfield is a tenanted farm owned by the National Trust. It is an organic mixed farm with cattle, sheep, ponies and arable enterprises. It extends to 240 acres. The farm is in a Higher Level Stewardship agreement and has a number of different habitats including lowland grazing marshes and wet woodland. There is an education building and nature trail following a circular route around the farm. The farm can cater for a number of educational activities and a Teachers Pack is available on request.