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<br /> <br />all transpiration and evaporation from lands on which there is vegetation of <br />any kind) whether agri'cultural crops or native vegetation, plus evaporation <br />from bare and idle land and from water surfaces. In some basins the amount <br />of water used in evaporation and transpiration by native vegetation is <br />greater than the amount consumed by irrigated crops. <br /> <br />Consumptive use by water-loving natural vegetation such as phreatophytes <br />is increasing in the Colorado River Basin. Phreatophytes comprise a great <br />variety, ranging from saltgrass to cottonwood trees. River-bottom growths) <br />such as salt cedars (Tamarisk), cottonwoods, willows (Baccharis) and tules, <br />consume more water per given area than irrigated crops. In the Pecos River <br />Joint Investigation the Division of' Irrigation estimated that 61,000 acre- <br />feet of water were consumed in 1939 by 13,000 acres of salt cedar. The <br />Pacific Southwest Federal Inter-Agency Technical Committee and the New Mexico <br />Salt Cedar Action Committee have set up subcommittees to study the control of <br />phreatoph;rtes. Use of water by these water-loving plants ha.s been measure.d <br />in several river basins by the Division of Irrigation Engineering and Water <br />Conservation and the U. S. Geological Survey. Additional information is needed <br />on water use by phreatophytes and replacement vegetation. <br /> <br />A report entitled "Soil Conservation Service Assistance to Irrigation <br />Agricult~e in the Western United States" was issued in November) 1952 by the <br />Department of Agriculture. Extracts relative to work with soil conservation <br />districts, assistance to farmers, water-supply forecasting and irrigation <br />research are as follows: <br /> <br />"The Soil Conservation Service has supplied technical <br />assistance for many years to irrigation farmers) <br />including settlers on proJect areas developed by the <br />Bureau of Reclamation. It has also aided hundreds of <br />small farmer-operated irrigation districts or groups <br />which lack engineering or.other technical facilities. <br /> <br />"Service assistance has consisted mainly of te.chnical <br />help in engineering planning and design, but has also <br />included help on problems of surface and ground-water <br />supply, soil management) cropping systems) and many <br />related aspects of profitable irrigation farming. The <br />Service has assumed leadership in most of the Western <br />.States in forecasting seasonal water supply from <br />cooperative snow surveys. Moreover, it has carried <br />on an aggressive program of irrigation research to <br />develop more efficient and economical methods of water <br />supply) conveyance, distribution, and application on <br />the farm . . . <br /> <br />"The Soil Conservation Service makes its help available <br />through soil conservation districts, which are local <br />governmental units organized under State laws and <br />administered by farmers and ranchers. The Service <br />cooperates with these districts under memoranda of under- <br />standing as a means of helping; them to plan and carry out <br />their programs of soil and water conservation and numagement, <br />including improvement of group irrigation facilities as <br />needed and recommended by the districts . . . <br /> <br />-11- <br />