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Sagebrush Reference Area, increase in cover in 1990, following partial abatement of drought, was lower than the reclaimed areas, while in 1991, Sagebrush Reference Area recovery exceeded that of the reclaimed areas. In the Mountain Brush Reference Area, where the woody plant cover is a large part of total cover, the total vegetation cover continued to fall in 1990, when all other sampled areas were on the rise; 1991 showed a further slight decrease in woody cover along with a large increase in herbaceous cover. The reclaimed areas are dominated by herbaceous species and the Sagebrush Reference Area also has a heavy herbaceous component. It is speculated that the herbaceous species are more quickly responsive to changes in climatic conditions than are shrubs, especially the tall shrubs that dominate cover in the mountain brush community, perhaps because these woody species generally root more deeply and may have greater carbohydrate reserves. In addition, the atypically mesic conditions of the Mountain Brush Reference Area may further buffer cover values in this area from the effects of drought. Nonetheless, the effects of drought may finally have shown themselves in the decrease of woody cover of the Mountain Brush Reference Area in 1990 and 1991 coincident with an increase of herbaceous cover during years of apparent amelioration of drought conditions. • The lag effect apparent in the woody cover of the Mountain Brush Reference Area, and to some degree in the Sagebrush Reference Area, may lead to a lack of proportional response to climatic conditions of a given year, thus compromising one of the basic assumptions regarding reference areas, and certainly questioning the use of areas dominated by woody vegetation to set annual standards for primarily herbaceous reclaimed areas. Production Only the herbaceous component was sampled for annual production in both the reclaimed and reference areas. Because the reference areas are both dominated by woody plants, the herbaceous component of production is small and is greatly exceeded by the production of the reclaimed areas where woody plants comprise only a small amount of total vegetation composition (Figure 2). Whether or not the large annual production of the reclaimed areas equals or exceeds the total (woody plus herbaceous) annual production of the reference areas is unknown. .~ 13