1999-03-08_PERMIT FILE - M1999025

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U. DEPARTMENT OF AGAICULTURfi PAGE 2 OP 2 NA RESOVRCES CONSERVATION SERVICE • • OB/1T/98 E~ote -- RANGELAND PRODVCTIVITY AND CNRACTEA I5TIC PLANT COMMUNITIES I rase that have similar cl ima[e and topography, diEf erencee in the kind and amount of vegetation produced on rangeland are closely related to Che kind of soil. Ef Eect Sve manag emenC is based on the rela[ionah ip between t ~eoils and vegetation and water. This report shows, for each Boil, the range Bite; the total amual p act ion of vegetation in favorable, normal, and unfavorable years; the characteriet is vegetation; and the a age percentage of each apes iee. Only those soils that are used ae rangeland or are suited to use as rangeland are listed. An explanation of the column headings in this report fall owe. RI~E SITE ie a distinctive kind of rangeland that produeee a characteristic natural plan[ community that differs from natural plant comminitiee on other range sites in kind, amount and proportion oP range plants. The re la[ione hip betweeen voile and vegetation was ascertained during this survey; [hue, range sites generally c~be determined directly from Che soil map. Soil properties that affect moisture supply and plant nue riente h the greatest Snf luence on the productivity of range plants. Soil reaction, salt content, and a seasonal high water table are also important. T PRODUCTION ie the amount of vegetation Ghat can be expected Co grow annually on well managed ra ngelantl t ie supporting the potential natural plant community. IC includes all vegetation, whether or not it is palatable to grazing animals. I[ includes the current yea r'e growth of leaves, twigs, and fruits of woody p [e. It does not inclutle the increase in et em dlametez of arses and shrubs. I e expressed in pounds per acre of air-dry vegetation Eor favorable, normal, and unfavorable years. In a favorable year, the amount and distribution of precipitation and the temperatures make growing conditions substantially better Chan average. In a normal year, growing conditions are about average. In an unfavorable y growing conditions are well below average, generally because of low available soil moisture. Dry weight i he total annual yield per acre of air-dry vegetation. Yiel de are adj ueted to a common pe rcen[ of air-dry moisture content. The relat icnehip of green weigh[ [o air-dry weight varies according to each factors ae e sure, amount of shade, recent rains, and uneea eonable dry periods. CTERIS TIC VEGETATION The graae ee, forbe, and shrubs that nuke up moat of [he potential natural plan[ community on each Boil ie listed by common name. U~r COMPOSITION [he expected percentage of the total annual production is given for each spec iee nuking up the characteristic vegetation. The amount that can be used ae forage depends on the kinds of grazing animals and on the grazing season. R~e management requires a knowledge of the kinds of Boil and of the potential natural plant community. IC also requires an evaluation of the present range condition. Range condition ie determined by comparing the p ant plant community with the potential natural plant community os a particular range site. The more c~ely the exieting community resembles the potential community, [he better the range condition. Range c ition ie an ecological rating only. The objective in range management ie to control grazing eo [hat the plants growing on a site are about the same in kind and amount ae Che potential natural plant community for t~ site. Such management generally results in the optimum production of vegetation, control of undesl rable b h species, conservation of water, and control of erosion. Sometimes, however, a range condition somewhat b w the potential meets grazing needs, provides wildl iEe habitat, and protects soil and water resources. 1 1