Tile drainage

In agriculture, tile drainage is a type of drainage system that removes excess water from soil below the surface. Whereas irrigation is the practice of adding additional water when the soil is naturally too dry, drainage brings soil moisture levels down for optimal crop growth. While surface water can be drained via pumping and/or open ditches, tile drainage is often the best recourse for subsurface water.

Tile drainage got its name from tiles made from fired clay (ceramic), similar to terracotta pipes but not necessarily in a pipe shape. In the 19th century a C-channel tile atop a flat tile (mug and sole, respectively) were often used. Today, however, tile drainage can be any system operating on the same principle, often with plastic tubing called "tile line". Precast concrete and ceramic are still used as well.

Too much subsurface water can be counterproductive to agriculture by preventing root development, and inhibiting the growth of crops. Too much water can also limit access to the land, particularly by farm machinery. In terms of access, most modern agriculture depends on the use of large machinery—tractors and implements—to prepare the seedbed, plant the crop, compaction.

Most crops require specific soil moisture conditions, and do not grow well in wet, "mucky" soil. Even in soil that isn't "mucky" the roots of most plants will not grow much deeper than the water table. Early in the growing season when water is in ample supply, plants are small and don't require much water. During this time, the plants do not need to develop their roots to "reach" for the water. As the plants grow and use more water during the growing season water becomes more scarce. During this time, the water table starts to fall. Plants suddenly need to start developing roots to reach to the water. During dry times, the water table can fall faster than the plants can develop roots to "reach" for the water. This can seriously stress the plants.

By adding drain tile, the water table is effectively lowered, and plants can properly develop their roots. The lack of water saturation allows oxygen to exist in the soil around the roots. Drain tile prevents the roots from being under the water table during wet periods that could cause excessive plant stress. By removing excessive water, crops use water they have more effectively.

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Wikipedia