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New Concepts for Assessment of Rangeland Condition New concepts for assessment of rangeland condition Item Type text; Article Authors Adams, D. C.; Short, R. E.; Pfister, J. A.; Peterson, K. R.; Hudson, D. B. Citation Adams, D. C., Short, R. E., Pfister, J. A., Peterson, K. R., & Hudson, D. B. (1995). New concepts for assessment of rangeland condition. Journal of Range Management, 48(3), 271-282. DOI 10.2307/4002433 Publisher Society for Range Management Journal Journal of Range Management Rights Copyright © Society for Range Management. Download date 02/10/2021 12:05:39 Item License http://rightsstatements.org/vocab/InC/1.0/ Version Final published version Link to Item http://hdl.handle.net/10150/644429 J. Range Manage. 48:271-282 May 1995 NEW CONCEPTS FOR ASSESSMENT OF RANGELAND CONDITION TASK GROUP ON UNITY IN CONCEPTS AND TERMINOLOGY COMRfITTEE hlEhlBERS E. Lamar Smith Phillip Sims Dave Franzen University of Arizona USDA/ARS U.S. Fish and Wildlife Service Tucson. Arizona Woodward, Oklahoma Lakeview, Oregon 1989-94 1989-94 1989-91 Chairman 1989-92 Ray Smith Milt Suthers Patricia S. Johnson Bureau of Indian Affairs U.S. Fish and Wildlife Service South Dakota State Univ. Herndon, Virginia Evergreen. Colorado Brookings, South Dakota 1989-9-l 1991-91 1989-9-l Chairman 1992-94 Len Volland John Willoughby U.S. Forest Service Bureau of Land Management George Ruyle Portland, Oregon Sacramento, California University of Arizona 1989-92 1989-91 Tucson, Arizona 1989-94 Miles Hemstrom Ned Habich U.S. Forest Service Bureau of Land Management Fred Smeins Lakewood, Colorado Lakewood, Colorado Tesas A&h,1 University 1992-94 1992-94 College Station, Tesos 19&9-94 Everet Bainter Tom Gwen Soil Conservation Service National Park Service Dick Loper Casper, Wyoming San Francisco, California Consultant 1989-92 1992-93 Lander. Wyoming 1989-9-l Arnold Mendenhall Jennifer Haley Soil Conservation Service National Park Service Dick Whetsell Lincoln, Nebraska Boulder City, Nevada Rancher 1991-92 1993-94 Pnwhuska. Oklahoma 19&9-94 Keith Wadman Soil Conservation Service Dennis Child Washington, D.C. USDA/ARS 1992-9-l Washington, D.C. 1959-92 Abstract tion of the status of rangelands. These concepts are based on the premise that the most important and basic physical Range condition score or classification does not tell us, in a resource on each ecological site is the soil. If sufficient soil is general sense, much of what managers and the public want to lost from an ecological site, the potential of the site is know about rangelands. Range condition is not a reliable changed. The Task Group made three recommendations, indicator, across all rangelands, of biodiversity, erosion which were adopted by the SRM: 1) evaluations of range- potential, nutrient cycling, value for wildlife species, or pro- lands should be made from the basis of the same land unit ductivity. Succession, the basis for the current concept of classification, ecological site; 2) plant communities likely to range condition is not an adequate yardstick for evaluation of occur on a site should be evaluated for protection of that site rangelands. The Society for Range Management (SRM) against accelerated erosion (Site Conservation Rating, established the Task Group on Unity in Concepts and [SCR]); and 3) selection of a Desired Plant Community (DPC) Terminology which has developed new concepts for evalua- for an ecological site should be made considering both SCR and management objectives for that site. Visual e\;lmplrh of sxne of thr\r concept\ ~111appear in an article to be pub- Key Words: Range Condition, Desired Plant Community, Site Iishrd in Rqyrhds Vol. 17(3):85-92, June 1995. Conservation Threshold, Sustainability, Ecological Site, Soil Erosion 271 JOURNAL OF RANGE MANAGEMENT 48(3), May 1995 Sustainable land use is the fundamental premise upon which Trend in the United States--19S9” (SRM 19S9) two years after management of rangelands, and other critically important natural publication of that report. resources, is based. The concept that we should manage land to 4. Review and publish an updated version of glossary terms maintain or enhance its productivity for future generations is not related to range classification, inventory, and monitoring at the new. But seldom in the short history of rangeland management same time as the assignment listed above. has the “condition” of the rangelands, especially public range- lands. attracted so much attention. One of the stated objectives of 5. Stay in close communication with SRM members on the the sweeping changes in grazing regulations and grazing fees pro- National Academy of Science committee concerning status and posed in Rangeland Reform ‘94 was to “accelerate restoration and progress. improvement of public rangelands” (USDI/USDA. 1994). This report is based on the work of the UCT on the first, sec- although no consistent criteria were provided for deciding ond, and fourth of the assignments above. The recommended def- whether such “improvement” had occurred. initions of terms relating to rangeland assessment are given in While nearly everyone agrees that early uncontrolled livestock Appendis A. After some deliberation, the UCT decided that it grazing resulted in major impacts on rangeland soils and vegeta- would not be useful to pursue the third assignment, updating the tion, there is little agreement on the measures of status and trends SRM’s report on range condition, because essentially no addition- under current management. Most professional rangeland man- al information was available on which to base such an update. agers and scientists agree with the widely quoted statement of The UCT maintained close liaison with the National Academy of Thad Box that “rangelands are in the best condition they have Sciences/National Research Council committee (NAS/NRC) been in this century.” Range condition data (e.g., SRM 19X9) formed at about the same time which eventually published a indicate that trend in range condition is up or static on about ‘85% report on “range health” (NRC 1994). Two members of the UCT of U.S. rangelands, public and private. These data, combined also served on the NASMRC committee. Copies of all meeting with numerous photographic records and personal experience, notes, draft reports, definitions, and other work of the UCT were lead to the conclusion that there has been general improvement in sent to the NAYNRC committee as they were done. Thus the the condition of rangelands since passage of the Taylor Grazing NAS/NRC committee was fully informed of the direction and Act. progress of the UCT, but this was a one-way exchange. Due to However, others disagree. Critics point out that the same data policies of the National Academy of Sciences, the UCT did not show that most public rangelands are in “poor” or “fair” condition see any of the work of the NAS committee until final publication and conclude that this situation indicates a failure of current man- of the Rnngelund Healrh book in 1994. Membership of UCT was agement and a need for drastic action as proposed, for example, chosen to insure representation of major federal agencies con- in Rangeland Reform ‘94 (USDLIUSDA 1994). The data are used ducting rangeland assessments, the academic community, and as the basis for claiming that soil erosion, wildlife habitat, biodi- private industry to provide for different perspectives and opportu- venity, and other values are being degraded or destroyed on our nity for feedback from a broad cross-section of SRM members rangelands as a result of livestock grazing (e.g., Wald and and others. Alberswerth 19S5, Comptroller General 1977, Dregne 19S3). Even the BLM stated that ranges in “fair” and “poor” condition TRADITIONAL RANGE CONDITION ASSESSMENT were “producing far below their potential” and were, therefore, Current approaches to rangeland condition assessment have “unsatisfactory” (BLM 1979). their roots in the observations of Sampson (1919). He related This kind of confusion and disagreement led the Society for stages of secondary succession to range condition classes pro- Range Management (SRM) to establish, first, the Range duced by livestock grazing. Heavy grazing caused a shift to lower Inventory Standardization Committee in 1978 (RISC 19X3) and successional stages and reduction or absence of grazing allowed then the Task Group on Unity in Concepts and Terminology successionto proceed to higher stages. This model was based on (UCT) in 1989. The recommendations in the report of the “Unity” the concepts of succession espoused by Clements (19 16). Task Group (UCT 1991) were adopted as policy by the Society Concepts of rangeland condition and trend and range sites for Range Management’s Board of Directors in July, 1991. The evolved over the next 30 years and were elaborated into opera- 1991 report of the Task Group is the basis for the concepts and tional procedures by Dyksterhuis (1949) and Parker (1954). recommendations presented in this paper. Some additional clarifi- Concepts and procedures have differed among the various agen- cation and literature citations are included in the present report cies (Soil Conservation Service, Bureau of Land Management, that were not in the original 199 1 Tak Group Report. and Forest Service) and have evolved within agencies over time. These differences make it difficult to compare data among agen- MISSION OF THE TASK GROUP cies or to establish changes over time. Nevertheless, all the The Task Group on Unity in Concepts and Terminology (UCT) approaches used have been founded on the same basic model of was formed in 1989 and assigned the following tasks: Clementsian succession proposed by Sampson (1919), and this 1. Continue professional dialogue on terminology, ecological remains the basis for evaluating “ecological status” by all three concepts, and use interpretations of ecological data relating to agencies today. rangeland classification, inventory and monitoring. In general, current approaches to rangeland condition rely on comparisons of species composition (relative biomass) of present 2.
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