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g/M2 production, and silver sagebrush Artemisia cana) with 5.27% ground cover and 4.30 g/M2 production. The
<br />understory consists mainly of big bluegrass (Loa amala), slender wheatgrass (Aeroovron Trachvcaulum), mulesears
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<br />dock W ethia amplexicaulis), Idaho fescue Festuca idahoensis), and western yarrow(Achille a millefolium)
<br />accounting for 18.00%, 5.47%, 5.13%, 4.73%, and 4.53% of the ground cover, respectively.
<br />Total shrub stratum variables averaged 25.19% ground cover, 87.88 g/m2 (784 lbs/acre) production, and a density
<br />of 13,554.8 shrubs or stems per acre. Herbaceous stratum variables averaged 34.06% ground cover by grasses and
<br />16.85% ground cover by forbs, 37.14 g/m2 (331 lbs/acre) production by grasses and 22.59 g/M2 (202 lbs/acre)
<br />production by forbs. The sagebrush community's overall variables are 76.1% vegetative cover, 149.18 g/m2 (1331
<br />lbs/acre) production, and 13,554.8 shrubs per acre for woody plant density. The diversity index as calculated by
<br />Shannon et al. (1973) for the entire community is 1.1199.
<br />Sagebrush vegetation type variables as presented above were determined from statistically adequate sampling.
<br />Sample parameters for each variable are presented in Table 27, Summary of Statistical Information.
<br />The sagebrush reference area used for this permit application is the same reference area as that being used for the
<br />79-177 permit held by CYCC. Both CYCC and TCC are subsidiaries of Cyprus Western, therefore, management
<br />of this reference area will be properly maintained. Map 18, Premining Vegetation, shows the location of this
<br />reference area. Table 28, Sagebrush Reference Area Vegetation Type, presents the data obtained from adequate
<br />sampling for the variables of ground cover, production, and woody plant density from this area. Performance of
<br />statistical t-tests for these three variables between the pre -disturbance area and the reference area show the
<br />reference area to be the same as the pre -disturbance vegetation type. The two -tailed t-test at the a = 0.05 level gave
<br />t values of 0.270 for cover, 0.638 for production, and 0.271 for woody plant density.
<br />Based on the data obtained in this study the carrying capacity of the sagebrush community within the proposed
<br />permit area is 4.7 acres/AUM, based on a utilization rate of 50% of the usable grasses and forbs and 5% of the
<br />• shrubs at a consumption rate of 1,000 lbs/AUM.
<br />Sap-ebrush/Meadow
<br />The sagebrush/meadow is a co -dominated vegetation type which only exists along the broad bottomland terraces of
<br />the Fish Creek floodplain and along certain portions of Foidel Creek within the proposed permit area. There
<br />are 471 acres or 3.7 percent of the proposed permit area covered by this type. Downstream along Fish Creek and
<br />well below the proposed permit area, this community has, at various locations, been converted to agricultural land
<br />uses. Primary efforts are toward pasture haylands. There will be no disturbance to the sagebrush/meadow
<br />vegetation type for approximately 15 years (beginning date 1983). At that time, it is expected that access roads will
<br />cross the Fish Creek flood plain at two locations, one in the NE'/, of Section 10, Township 5 North, Range 86 West
<br />and the other in NW'/. of Section 19, Township 4 North, Range 86 West. It is expected that total disturbance will
<br />be less than 0.25 acres.
<br />As identified in Table 24, Vegetation -Soil Correlation, and Table 29, Characteristics of Soils Underlying the
<br />Sagebrush/Meadow Vegetation Type, three soils are found below the community. These soils are always deep and
<br />range from well drained on the upper terraces to permanently wet in the lowest bottoms. Parent material is always
<br />mixed alluvium, and permeability is always moderate unless it is permanently wet. Available water capacity
<br />ranges from moderate to permanently wet. The land capability subclasses of these soils are varied ranging from
<br />Vle to Vc to Vw (see land use discussion under Rule 2.04.3 for further information regarding land capability
<br />subclasses).
<br />As identified on Table 30, Sagebrush/Meadow Vegetation T?pe, the shrub stratum where it exists is dominated by
<br />silver sagebrush with 12.10% ground cover and 38.21 g/m production and mountain big sagebrush with 5.00%
<br />• ground cover and 18.84 g/m2 production. The co -dominant under -story consists mainly of Kentucky bluegrass
<br />APPRoVRp APR 2 4 7�f�n
<br />Permit Renewal No. 3 2.04-55 I 799
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