1999-04-21_PERMIT FILE - M1999024

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U.S. UEPARTHENT OF AGRICULTURE NATURAL~RESUURCEs CONSERVATION SERVICE PAGE i UP 2 • • U6/il/98 Emm~ate -- RANGELAND FkUUUCTIVITY ANU LHRACTEkISTIC PLANT CONNUNITIEs In areas that have similar climate end topography, differences in the kind and amount of vegetation produced on rangeland ere closely related to the kind of soil. Effective management is based on the relationship between the soils and vegetation and voter. This report shoos, for each soil, the range site; the total annual production of vegetation in favorable, normal, and unfavorable years; the characteristic vegetation; and the average percentage of each species. Only those soils that are used as rangeland or are suited to use as rangeland are listed. An ezplanation of the column headings in this report follows. kANGE SITE is a distinctive kind of rangeland that produces a characteristic natural plant community that dttfers from natural giant communities on other range sites in kind, amount and proportion of range plants. The relationship betveeen 50115 and Vegetatl0n was ascertained during this Survey; thU S, range Sltea generally can be determined directly from the soil map. Soil properties that affect moisture supply and giant nutrients have the greatest influence on the productivity of range plants. 'soil reaction, salt content, and a seasonal high eater table are also important. TOTAL PkUUUCiION is the amount of vegetation that can be expected io grow annually on well managed rangeland that is supporting the potential natural plant community. It includes all vegetation, whether or not it is palatable t0 gf8xlnq 8nlmala. It 1nCludeS the current year's 9roVth Of have 5, t~lgs, and frUlts O} g00dy plants. It does not include the increase in stem diameter of trees and shrubs. li is ezpressed in pounds per acre of air-dry vegetation for favorable, normal, end unfavorable years. In a favorable year, the amount and distribution of precipitation end the temperatures make growing conditions substantially better than average. In a normal rear, growing conditions ere about average. In an unfavorable year, growing conditions are well below average, generally because of Lau available soil moisture. Orr veight is the total annual yield per acre of air-dry vegetation. Yields are adjusted to a common percent of air-dry moisture content. The relationship of preen veight to air-dry veight varies according to such factors as ezposure, amount of shade, recent rains, and unseasonable dry periods. CHARACTERISTIC VEGETATION the grasses, fortis, and shrubs that make up most of the potential natural plant community on each soil is listed by common name. Under CUMPOSITiON the ezpected percentage of the total annual production is given for each species making up the characteristic vegetation. The amount that can be used es forage depends an the kinds of grazing animals end on the grazing season. Range management requires a knowledge of the kinds of soil and of the potential natural plant community. It also requires an evaluation of the present range condition. Range condition is determined by comparing the Dresent Diant community with the Dotential natural plant community on a particular range site. The more closely the existing community resembles the potential community, the better the range condition. Range COnd1t10n 15 8n eCOlOg1CBl rating Only. The objective in range management 15 t0 COmtr01 gra21m9 50 [hat the giants growing on a site are about the same in kind and amount as the Dotential natural plant community for that site. SUCK management generally results in the Optimum production of vegetation, control of undesirable brush species, conservation of water, and control of erosion. sometimes, however, a range condition somewhat belov the potential meets grazing needs, provides vildlife habitat, end protects soli and voter resources.