Putting hay into the barn is preferable to stacking. When hay is stacked for any considerable time more or less loss occurs through exposure to sun and rain unless the stack is covered. In many sections hay barns would soon pay for themselves. Yet many farmers will continue to stack part or all of their hay until they become convinced that hay barns or sheds are a good investment. This bulletin, therefore, describes the different types of stackers in use, states the conditions favorable for each type, and points out the saving of man labor made possible by the use of the stacker.