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. ~ ( ~ . . ~ (, - .~ c - 5 - The area between the High Line Canal and the foot of the Little Book Cliffs lies at elevations between 4,750 and 5,800 feet. It contains) relat~vely smooth gravel-capped mesas alternating with shale badlands and relatively steep dry ~~shes. The surfaces of the higher mesas slope gently southwestward and are underlain by a protective mantle of gravel and larger rock fragments. These mesas represent remnants of former erosion surfaces lying at various levels fram 50 to 400 feet above the present stream channels. The shale badlands occupy irregular areas between the mesas and are most sharply dissected along the foot of the Little Book Cliffs and in places where the gravel cover of former mesas has been removed by erosion, leaving steep, narrow shale ridges. A considerable portion of the shale area consists of rolling uplands on which an intricate pattern of shallow ravines and gullies has been cut. The area below the High Line Canal is between 4,550 and 4,750 feet in elevation and is part of a broad alluvial plain formed by coalescing alluvial fans and stream floodplains at the lower ends of dry washes along the north side of the Co19rado River. This plain is about 3 miles in width along Indian Wash and contains most of the irrigated land in the watershed as well as the City of Grand Junction. Soils.- The soils in the watershed are developed on parent materials derived mainly fram the Mancos shale with same influence locally from sandstones of the Mesaverde group. The soils are all light-colored and typical of those developed under a desert climate in this region. In their virgin state, the soils contain a very low percentage of organic matter. They generally'.have a high content of lime carbonate, gypsum, and salts of sodium, potassium, magnesium, and iron. In the area above the High Line Canal, the soils range widely in stage of development. Raw shale occurs at the surface on most of the steeper slopes. Thin residual soils are present on the more gently rolling areas underlain by shale. Soils on the floodplains of the larger streams have had only a short period of time for development and have no definite concentration of lime or clay in the subsoil. On the higher terraces and mesas, soils are developed on thin eolian deposits overlying the gravels. These soils have weathered a long time without being subjected to severe erosion or to deposition, and as a result, have high concentrations of lime in the subsoil. In places, they have a subsoil somewhat finer textured than the surface soil. The soils on the mesas are moderately deep and are characterized by a pronounced reddish tinge.