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Herbaceous production of the Mountain Brush reference area from 1987 to 2004 has averaged <br />778 Ib/ac. The 2004 level of 664 Ib/ac was significantly (at the 90 percent level of confidence) <br />lower than the long-term average; conversely, in 2003 the observed 1089 Ib/ac was significantly <br />greater than the average (at the 99 percent level). Herbaceous production of the Sagebrush <br />reference area over this period was 1223 fb/ac. 2004 herbaceous production of 1024 Ib/ac was, <br />like cover, significantly below average. And, like cover, the 2003 level of 1947 Ib/ac was <br />significantly above the long-term average. 2004 production in the Wadge Pasture reclaimed area <br />at 2493 Ib/ac was significantly below the long-term (13 year) average of 3005 Ib/ac. The 2003 <br />production level of 3422 Ib/ac was greater than average at 80 percent confidence. <br />The proportion of Wadge Pasture production contributed by alfalfa in 2004 was 12.3%, down from <br />31.7% in 2003 as well as 2002 (14.7%) and 2001 (22.6%). <br />Woody Plant Density <br />Figure 3 graphically presents shrub density totals for reclaimed areas sampled in 2004. The <br />1997 reclamation area averaged 834 woody plant stems per acre, about half of which was <br />serviceberry and mountain snowberry. Relative to the technical standard of 1000 stems per acre, <br />three of the five average densities of reclaimed areas (plus 90 % confidence intervals) reached <br />90% of that standard (900 stems per acre). The Wadge Pasture value of 955 stems per acre <br />exceeded the standard for the first time in the 17-year record. <br />The long-running record of woody plant density in the Wadge and PECOCO Pasture units is <br />tabulated below: <br /> 1985 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 <br />Wadge NA NA 322 476 408 288 344 356 271 182 239 210 547 227 393 360 502 591 955 <br />(stemslac) <br />PECOCO NA NA NA NA NA NA NA 295 NA NA 376 NA 150 NA NA 215 627 227 506 <br />(stems/ac) - <br />From this record, it is apparent that during the period 1988 through 2001 there have been <br />fluctuations in density values over the years in Wadge Pasture that have not constituted <br />consistent trends upward or downward. The apparent upward trend in 2002, 20003, and 2004 <br />would seem to be different. A comparison of these woody plant density data with climate records <br />(Figures 7a, 8a, and 9a) and records of cover and production (above) suggests that there is an <br />inverse relation between favorable growing conditions and the prevalence of shrubs. When <br />moisture is adequate to allow grasses and other herbaceous species to grow vigorously, the <br />competitive side effects are devastating to shrub numbers. Conversely, when dry times are <br />intense and of sufficiently long duration, the shrub numbers rise. Sample sizes in Wadge <br />14 <br />