Rustic barns, tall silos, and other farm buildings long shaped the rural landscape, but their disappearance reflects changing agriculture as large farming operations gradually replace small family farms. In the Sheyenne River Valley, many small farms still retain old-style outbuildings and residences that preserve signature elements of that older landscape. North Dakota's oldest barn roof style is the simple gable, followed over time by the more space-efficient gambrel roof recognized as the typical American barn roof, while gothic barn roofs also became popular through mail-order firms such as Sears, Roebuck and Co. Traditional wooden barns have largely been replaced by metal sheds, and silos, usually made of concrete or ceramic block and more rarely of brick or wood, were used and sometimes still are used for grain or feed storage. Traditional farmhouses often featured Victorian style, gable fronts, and open porches, though many surviving houses now have enclosed porches. Outhouses were once common on farms and homesteads. Many farms still have wooden granaries, though most are now used for general storage rather than grain, and grain was traditionally hand-shoveled into them through large side-opening doors, small metal hatches on the roof, or small wood doors in the gable ends. Government regulations no longer allow the use of wooden granaries, so steel grain bins resembling short steel silos are now used. Some modern farms still use wind power to pump water for livestock, with old-style windmills generating roughly two to eight horsepower, or one and a half to six kilowatts. A typical farm complex included multiple buildings, each with a specific purpose.