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CD ,.~ The lands of the Conejos Division are included within the boundaries ~~ of the Cenejos Water Conservancy District which is situated in the south- ~J western portion of the extensive San Luis Valley in south-central Colorado. l..:.> They occur on bottom lands, low terraces, and broad gently sloping outwash C=> plains adjacent to the course of the COnejos River and its affluents, and are composed of variable alluvium -- cobble, gravel, sand and finer mate- rials -- eroded from igneous formations of the San Juanl<lountains. LANDs AND sons Soils and Topograpny The soils of the division are alluvial in orlgLn, pale brown to brownish-gray in color, range in texture from gravelly sandy loams to clays, and are recent to young in development, being le.rgely without distinct lay-, ers. The surface soils are neutral to slightly calcareous, the subsoil~ are slightly calcareous, and soluble salts are present in variable amounts depending upon the factors of Posjtion, drainage and inherent soil charac- teristics. On the basis of mode of formation and topographic position, there are two distinct groups of soils in the division: (1) The soils of the outwash plains are the most extensive, comprlslng a large proportion of the lands suitable for diversified crop production undor irrigation, and occupy- ing the bro'ad gently Sloping fans of outwash debris above the stream valleys. They are pale brown to gray in colo~, gravelly sandy loam to clay in text~re, and contain vari- able amounts of grilvel or cobble in the plow zone and throughout the prOfile. Surface and subsoil drainage are good te excessive in many placns, ~nd harmful accumulations of soluble salts do not occur except in lower-lying areas. Though low in organic matter content, these soils have proved relatively fertile, and their productive capacity is limited chiefly by the amount ef gravel or cobble in the plow zene, or by shallowness '>v"r the coarse substratUlll. (2) The soils of the recant flood plains are less extensive than the alluvial-fan Sails, but are fairly well distributed along the ceurse of the Conejos River and its tributaries. The surface seils are brownish-gpay (nearly black when wet), noncalcareous sandy loams te silty clay loams underlain by cearser alluvium or silty claY,loams and clays characteris_ tically mottled as a result of long-continued poor drainage. In many places gravel and cobble occur on the surface or in the upper soil horizons in amounts sufficient to render cultivation difficult if not impossible and productive capacity relatively low. These ,tracts comprise the major areas Jf pasture, meadow or marginal and nonarable lands and, in general, 2re not well suited fer diversified crep production. The topography of the lands is, in general, excellent for surface irrigation, inasmuch as a large proportion of land suitable for cropping under irrigation occupies a more or less continuous, extensive alluvial 16