Yields from five irrigation regimes that each applied 16 acre-inched acre were evaluated during a simulated drought year and for thesubsequenttwoseasonsunder full irrigation. Drought-year production was mildly reduced by regimes that produced smaller kernels. Much greater losses occurred in the season immediately following the drought due to reduced nut load. Applying a limited allotment of water early in the drought season proved less effective in limiting subsequent production losses than

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... gating at a lower rate but for a longer period of the drought season. Avoiding severe water stress during flower bud development (August and September) is critical for subsequent bloom and fruit set-A mature almond orchard in the interior valleys of California can use 36 to 38 acre-inches/ acre (hereafter referred to as inches) of water in an average weather year. During periods of drought, growers with wells can continue to pump groundwater to meet their irrigation needs, but growers serviced by irrigation districts may have their normal allocations reduced. Moreover, escalating competition from the municipal and environmental sec-tors has added pressure on what is essentially a fixed surface water supply. Whether tight water supplies are due to droughts or increased competition, many almond growers will periodically have to decide how best to manage smaller amounts of water than they normally use. Since there are about 400,000 acres of bearing almond orchards in California, the economic impact of poor drought-year water management is potentially severe.