ABSTRACT
Irrigation management includes deciding how much irrigation water to apply, and when to start and stop the irrigation. For any management decision, the choice of operation depends on what one wants to do. The simple answer may appear to be ‘‘put on some water,’’ but the choice is often more complex. For instance, one can attempt to maximize net return, minimize operating costs (especially labor), maximize yield, optimize limited water supply, minimize environmental risk, or optimize production under a limited irrigation system capacity. All of these may be constrained by regulations. In general, water supply and irrigation costs control the economics, so the best result is obtained by maximizing yield on all irrigated land, usually called the land-limiting case. In simple terms, one irrigates to avoid crop water stress.
