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<br />.... <br />en In the 1980 assessment of the forest and rangeland ?ituation, the Forest <br />(~ Service used a range condition classification of good, 61-100% of the <br />r0 potential; fair, 41-60%; poor, 21-40%; and very poor, '20% or less 1/. Table <br />3 shows the percentage of rangeland in each condition class for the six states <br />in Region VIII. About half is in the poor and very poor condition categories <br />and less than 20% is in good condition. This would indicate that serious soil <br />losses are occurring on about 100,000,000 acres of rangeland in the Region and <br />that runoff i~ ca~rying sediments, dissolved solids and other contaminants <br />into adjacent str'eams, lakes and reservoirs. <br /> <br />Table 4 lists the comparative soil losses from sheet and rill erosion in <br />tons per acre per year for cropland and non-federal rangeland for the six <br />states in Region VIII. These statistics were calculated by the U.S. <br />Department of Agriculture by use of the universal soil loss equation. No <br />comparable data is available for federal rangeland. <br /> <br />The Soil Conservation Service has established soil loss tolerance values <br />for all .soi1s. These range from 2 to 5 tons per acre per year. The soil loss <br />tolerance value is the maximum average annual soil loss that can be tolerated <br />indefinitely without interfering with sustained high production. (U.S. <br />Department of Agriculture 1980. Soil, Water, and Related Resources in the <br />U.S., 1980 appraisal Part I, p. 39). <br /> <br />Table 4 shows that an average of 72% of the cropland and 79% of the <br />non-federal rangeland in Region VIII are losing less than 2 tons of soil per <br />acre per year, and that 7.7% of the cropland and 10.7% of the rangeland lose <br />more than 5 tons per acre per year. The rate of soil loss does not differ <br />substantially between crop and rangeland, but acreage of all rangeland <br />(including federal) is three times greater than cropland acreage in the <br />Region. Thus runoff from rangeland becomes an important consideration in <br />water quality management. <br /> <br />2. Ranqe 1 and Po 11 utants <br /> <br />It is generally recognized that sediment produced by runoff is the most <br />significant pollutant from rangeland, but chemical or bacteriological <br />pollutants may originate on grazed lands also. These include dissolved <br />minerals, alkalinity, nutrients (phosphates and nitrates), and fecal coliform <br />and streptococcus organisms. Salt loading occurs in runoff from saline soils <br />and may be intensified by excessive grazing during the spring period. <br />Pesticides can become attached to sediments and be carried into stream <br />channe 1 s. <br /> <br />1/ USDA, Forest Service, 1980. An Assessment of the Forest and Rangeland <br />- Situation in the United States. p. 254. <br /> <br />- 9 - <br /> <br />