Work on root systems of forage plants has indicated that a knowledge of root relationships is fully as important in determining the actual conditions of ranges or pastures as is knowledge of the effects of grazing upon aboveground portions of plants. This is especially true in arid or semiarid regions since plants of these areas are frequently subjected to long periods of drought, high temperatures, and high wind velocities. Some xeric plants have a thickened cuticular layer, stomates that open only at night, and other mechanisms that prevent loss of water that is absorbed by the roots. However, in plants of the short grass plains an extensive root system is the primary means of obtaining water that is needed for life processes during perio...