The Arizona sentinel., 1896-05-16

of shel GiEa and Colorado rivers have for the most part deep sedimeataky soil of brownish, gray saniy loanl, resting, in most places, upon a gray clay subsoil at depth of from ten to twenty feet below the surface, The clay subsoil forms hard pan which is impervious to water. These soils have been slowly formed by the decomposition of shales, sandstones, marls. Emestones etc., mixed with or ganic and vegetable matter, shed down by the mighty rivers and have been gradually deposited during the course of centuries. The fertilizing hrovnish mud held in the wat tlof the Colorado and r'ia rivers rcsenbes that from the Nile. and i-- c;aaei5y varies from 0.1 to O.5 per cent, q. .ggA tne water vhen even considerably dscolor- ei by mud is good to drink resembling ill this res pect the Missouri river water A chemical analysis of the sediments Of the Colorado and Of the Nile exhibits a wonderful similarity in the constituent parts of each. That of the Colorado exhibiting a triie less potassa, most phosphoric acid and car bonade of limestone beds through which the Colo rade pesss. In other respects the sediment of the Colorado is almost identical with that of the Nile. It will be noticed therefore, that when this water is used for irrigation it is superior to artesian waters since it is constantly supplying the land with the rchestiertilizing elements Tie soil of the valleys is extremely rich in dedomposed vegetable matter and uncombined carbon, readily absorbing the aerial gases such especially, as oxygen, which en tering the soil, dccomposeS the organic matters that they can be taken up and nourish the plants which may De considered a leading feature in its fertility. It also readily takes up and retains moisture, while the rnness of it's particles affords every facility for percolation and the activity Of capillary action. In ts mechanical composition its particles are in state of very fine division, which renders it more productive than coarSer soils It acquiries heat readily in the daytime, and the loss of the heat at night s very gradual so that it re- mains always warm and is not subject to sudden changes of heat and cold. Besides it's essential sttuents of water, organic vegetable matter, sand and clay, chemical analysis shows that lime, soda, magnesia, iron, ammonia and available forms of nitrogen phosphorc acid and potash enter into composition in the proportions best adapted to add to it's fertility, though, of course is alwaJs the in soil analysis its composition varies in different localities and is not always constant.
 The soil of the upands, or mesas, lighter and more gravelly and in some places of lree, loamy, calcareoUs character. The mesa lands are warm and generous. They seem especially adapted for the grape olive and citrus fruits generally. Their soil contains more magnesia, lime or chalk than the bottom lands It never cracks and retains moisture admirably in summer. It is Of that character which will produce wine that will keep gcod for fifty or hundred years, and improve annually, not being liable to sour, exposure to the air, after year old, to become turbid and change color in the bottle or glass.
 We can safely say that the soil of Yuma County nowhere be surpassed, containing as it does all the essential elements of richness and fertility.