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OBJECTIVE • The objective of this technical note are: (1) to present a revised system for classifying the degree of accelerated erosion condition and (2) to give guidance on the field method for measuring the erosion condition class for a sample area. 'The revised classification system makes use of the same erosional features used to evaluate the degree of erosion for the past ten years. The degree of tilling and gullying are to be evaluated for every case where water is the dominant ero- sional agent. They will not be used in the evaluation for areas in which wind is the dominant erosional agent. It is expected that these changes will result in a higher degree of replication of results between individuals evaluating the same area, and a higher degree of uniformity in measured results for comparable conditions between different areas. Today, most of the erosion condition inventory work is being done as part of the SVIM inventory process. Many of the SVIM inventory crew members are not well trained in the causes and effects of erosion. Therefore, there have been requests for preparing a technical note that is easily understood by range conservationists, foresters, wild- life and fishery biologists, botanists, recreational specialists, as well as by hydrologists and soil scientists. A recommended reference for more detailed information about the causes and effects of erosion "~ is Rangeland Hydrology (Branson et. al., 1972). ,Classification System • Field observations are made on seven surface features that are visual- ly affected by current wind and water erosion activity: soil move- ment, surface litter, surface rock fragments, pedestalling, flow patterns, rills, and gullies. All of these are not expected to be presenC in the same degree. In certain situations, some, like surface rock fragments, may not be potentially present. When [his occurs, adjustments are made as will be shown in Illustrations 1 through 3. While observing these features, the total area to be represented must be kept in mind as significant variation may occur within the area. The meaning of terms used in this procedure may not be the same for all of us. To aid you in understanding the procedure, these terms are defined in Appendix 1, Glossary of Terms. Procedure The five (5) steps follow: 1. The initial step in following this procedure is to determine of the intensity of erosion inventory needed. This may vary from a general erosion inventory, such as the Bureau completed in 1978 on most public lands, or a specific erosion inventory on a small area such as a site writeup area, comparison area, particular land treatment area, or soil type delineation. See BLM Manual, • Sections 7317.12 and 4412.14D9, for current guidance for water- 5