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of 79 water developements, and chaining] 000 acres of pinyon-juniper woodland, in combination with the modifications found in "Ib". Treatment effects and results would be the same as those in treatment la and ab. o o 0>:>- m 2) Sagebrush Chopping - Sagebrush chopping is accomplished by pulling a rolling brush cutter, consisting of a hoIlow, water f1l1ed drum equipped with several full-length cutting blades, behind a crawler tractor (Valentine, 1980). Under this treatment sagebrush is mechanically chopped, crushed, and left in place to act as a natural dam against overland flow. The treatment, as proposed for the Greater Sagers Wash Watershed, would involve "contour strip sagebrush chopping" where sagebrush is chopped and crushed in twelve foot wide strips following the contour. Strips are spaced 400 feet apart during the initial treatment. Two years after the initial treatment additional twelve foot wide strips are chopped and crushed making the overall spacing between strips 200 feet. The natural dam created by the chopped and crushed sagebrush would increase the effective ground cover and as a result would trap sediment and debris, decrease runoff velocities, increase infiltration, and decrease total runoff, It will also create a suitable environment for the quick re- establishment of sagebrush and other species. Although a large area would be affected by the sagebrush chopping only approximately 10% of the area will actual.ly be treated. 3) Pinyon-Juniper Chaining - Chaining is accomplished by dragging heavy anchor chain in a U-shape, half circle, or J-shape behind two crawler tractors traveling in a parallel direction (Valentine, 1980), Islands of trees are left in place at designated locations within the treatment area as shelter for wildlife. The treatment area is seeded with a mixture of grasses, forbs, and shrubs immediately following the chaining. ~ The effect of the treatment is to increase effective ground cover and available moisture by uprooting the trees and bringing the tree canopies and trunks into contact with the soil and by increasing grass, forb, and shrub production and overall species diversity. The increase in effective ground cover results in increased on site sediment retention, decreased runoff velocities, increased infLltration, and decreased total runoff, l 4) Contour Pits and Cisco Pits - Contour Pits are smal.l basins which are typical.ly 3 to 5 feet long, 8 to 12 inches wide, and 4 to 8 inches deep, The pits are constructed at regular intervals along the contour by pulling an eccentric disk pitting device behind a crawler tractor. Rows of pits are spaced 2 to 3 feet apart and the density of pits is approximately 600 per acre (Valentine, 1980). The effect of the contour pits is to hold runoff and sediment on site, and decrease runoff velocities. The pits result in increased infLltration, decreased runoff and runoff velocities, and increased on site sediment retention. Pitting often doubles absorption rates thereby reducing runoff during torrential rains (Valentine, 1980). ~ 36