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PRODUCTION <br />(Table B -14) <br />Total herbaceous production in 2012 was 239.1 pounds per acre. Of this, 224.8 pounds were attributable to <br />native perennial cool season grasses. Native perennial forbs contributed 10.7 pounds per acre. Native <br />annual and biennial forbs and introduced perennial forbs were each present with 1.8 pounds per acre. <br />DISCUSSION <br />Climatic Conditions <br />The year preceding 2011 sampling was characterized by a very wet fall and winter (precipitation in <br />December of 2010 totaled a record 2.98 inches), continuing in early spring with a very wet April and May <br />(Figure C -7b). June 2011 precipitation was below average with a return to above average precipitation in <br />July 2011. The abundant cold- season precipitation created above average snowpack levels for the region. <br />These wet months combined with a wet summer left precipitation total for the 12 months preceding <br />sampling well above average (Figure C -8b). In general, 2011 was the wettest and coolest observed in the <br />last 26 years. In contrast, the winter and spring preceding 2012 sampling was very dry, with precipitation <br />well below average (Figure C -7b). March, April, May and June of 2012 also had below average <br />precipitation. As a result, precipitation for the 12 months preceding sampling was the second lowest in the <br />last 26 years, with 2002 being the lowest (Figure C -8b). The first six months of 2012 were also the warmest <br />in the last 26 years (Figure C -11). <br />Sample Adequacy Calculations <br />Sample adequacy of total all -hit vegetation cover was achieved in each of the reference areas as well as <br />BRB -1 in 2012 (see below and Table C -4). In 2011, sample adequacy based on all -hit allowable <br />herbaceous cover was also achieved in BRB -1 and each of the reference areas except the Mountain Brush <br />Reference Area. Thus, in 2011, the alternative of using the upper 90% probability value of the mean was <br />exercised. In other words, after having established a reliable estimate of population variance having taken <br />18 samples in 2011, the maximum possible values of the mean (with 90% confidence) was taken to <br />represent the allowable herbaceous cover of the Mountain Brush Area. Details of the calculation of <br />allowable herbaceous cover for each area are provided in Tables G -1 through G -12. <br />23 <br />