About 25 woolly sheep who seasonally — for the past two years — leave barns to nibble on lawns at various central campus locations, are doing much more than mowing, fertilizing and improving the ecosystem. The sheep also are improving people’s mental health.About 25 woolly sheep who seasonally — for the past two years — leave barns to nibble on lawns at various central campus locations, are doing much more than mowing, fertilizing and improving the ecosystem. The sheep also are improving people’s mental health.