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Show PART II PRESENT STATUS OF IRRIGATION depending largely upon slope, water supply, soil characteristics, economics and the farmer or rancher. Generally, alfalfa is grown in areas which have an adequate water supply and is under better management than is permanent pasture or native hay. Corrugations or furrows, 1 to 3 feet apart, are developed during initial seeding, with small grain used as a companion crop. These corrugations or furrows may or may not "be maintained after growth is established. Alfalfa is irrigated five or more times a season, depending upon availability of water, climate, and other factors. Approximately 200,000 acres of irrigated land in the region are inten- sively cropped. Small grains and other close growing crops, comprising about 5 percent of the irrigated cropland in the region, are usually irrigated by the corrugation method. These crops, which usually are planted in the fall, receive three or more irrigations a season. Row crops, comprising about 6 percent of the irrigated cropland, are adapted to furrow irrigation. Speci- ality crops such as sugar beets and orchards are grown in the warmer cli- mates of Mesa, Delta, and Montrose Counties in Colorado and in the Price, Utah, and Farmington, N. Mex., Areas. These crops are produced under con- ditions of proper air drainage, a stable water supply, permanent irrigation structures, and a higher level of water management than crops used as feed for livestock. Of the 18,300 acres of orchard produced in the region, 75 percent is in Delta and Mesa Counties of western Colorado. Orchards are irrigated five to eight times a year with four to five small furrows between tree rows. The last irrigation during the growing season is applied 10 to 1^ days prior to harvest. Since trees need winter moisture, water is ap- plied again following harvest. Good water management is important for or- chards as excessive or insufficient irrigation will damage or kill trees. Heavy fruit harvest in New Mexico reflects good water management 18 |