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This study was conducted on the Jornada Experimental Range (JER) from 1938-2001. The study area is located on a bajada slope where typic Paleorthid soils have formed on an old alluvial fan. Vegetation is dominated by creosotebush, with honey mesquite (Prosopis glandulosa) and tarbush (Flourensia cernua) also present. Sixteen plots (21.3 m x 21.3 m) were established in 1938 in four rows of four plots per row with a buffer zone of 7.6 m between plots. All plots were sampled prior to treatment applications. Each plot was divided into east and west halves and 14 randomly located 10.65 m line intercept transects were sampled for shrub canopy cover and perennial grass basal cover in each half-plot. These plots were resampled in the same fashion in 1947, 1956, 1960, 1967, 1989, and 1995, using a separate set of randomly located transects in each sampling year. Treatments were factorially applied, yielding a control plot, single factor plots, and plots with varying degrees of combinations of factors. Original treatments applied to these 16 plots were clearing (hand removal of shrubs severed at ground surface), furrowing (shallow, hand raked furrows designed to trap surface water), seeding (broad-cas application of seeds of native perennials), and lagomorph exclusion. Poultry netting with a 2.5 cm mesh buried about 15 cm in the ground and extending above-ground about 75 cm was used to exclude lagomorphs. Shrubs (not including suffrutescents) have been removed from the cleared plots immediately following all resampling periods listed above. Seeded species were black grama, spike dropseed, mesa dropseed (Sporobolus flexuosus), and fourwing saltbush (Atriplex canescens). All treatments were applied after the initial vegetation measurements were recorded in 1938, except that the lagomorph exclusion fences were constructed in1939. Livestock were excluded from the study area in 1938, and the site has not been grazed by livestock at any time during the study period.