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Herbaceous production of the Mountain Brush reference area from 1987 to 2003 has averaged • 785 Ib/ac. The 2002 level of 435 Ib/ac was significantly (at the 99 percent level of confidence) lower than the long-term average; conversely, in 2003 the observed 1089 Ib/ac was significantly greater than the average (at the 99 percent level). Herbaceous production of the Sagebrush reference area over this period was 1237 Iblac. 2002 herbaceous production of 805 Ib/ac was, like cover, significantly below average. And, like cover, the 2003 level of 1947 Ib/ac was significantly above the long-term average. 2002 production in the Wadge Pasture reclaimed area at 808 Ib/ac was significantly below the long-term (13 year) average of 3005 Ib/ac. The 2003 production level of 3422 Ib/ac was greater than average at 80 percent confidence. The 2003 Wadge Pasture production was approximately 400 Ib/ac greater than the adjacent ungrazed 1987-1989 reclamation (see discussion above). The proportion of Wadge Pasture production contributed by alfalfa in 2003 was 31.7%, up from 2002 (14.7%) and 2001 (22.6%). It would appear that the past two years without grazing have allowed the alfalfa to make a recovery Woody Plant Density Figure 3 graphically presents shrub density totals for reclaimed areas sampled in 2003. The • 1996 reclamation area averaged 4282 woody plant stems per acre, mast of which was rubber rabbitbrush. Relative to the technical standard of 1000 stems per acre, none of the average densities of reclaimed areas reached 90% of that standard (900 stems per acre). The Wadge Pasture value of 591 stems per acre was the closest. The long-running record of woody plant density in the Wadge and PECOCO Pasture units is tabulated below: 1985 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 Wadge NA NA 322 476 408 288 344 356 271 182 239 270 547 227 393 360 502 591 (stems/ac) PECOCO NA NA NA NA NA NA NA 295 NA NA 376 NA 750 NA NA 215 627 227 (stemsrac) From this record, it is apparent that there have been fluctuations in density values over the years in Wadge Pasture that have not constituted consistent trends upward or downward. A comparison of these data with climate records (Figures 7a, 8a, and 9a) and records of cover and production (above) suggests that there is an inverse relation between favorable growing conditions and the prevalence of shrubs. When moisture is adequate to allow grasses and other herbaceous species to grow vigorously, the competitive side effects are devastating to shrub • numbers. Conversely, when dry times are intense and of sufficiently long duration, the shrub 15