The Arizona sentinel., 1895-03-23

O the Gila and Colorado rivers have foI the most ! part deep sedimentary soil of brownish, gray sandy lo2m, resting, in most places, upon gray clay subsol at a depth of from ten to twenty feet below the surface, The clay subsoil forms hard pan which is impervious to wtter. These soils have been slowly formed by the decomposition of shales sandstoncs, marls. lmestones, etc., mixed with or ganc and vegetable matter, washed down by the mighty rivers and have been gradually deposited during the course of centuries The fertil!zng brown.sn mud held in the water of the Colorado and Gila rivers resembles that from the Nile, and its quantity varies from O.1 to O.5 per cent, though the water when even considerably discolor- ed by mud is good to drink, resembling in this pect the Missouri river water. A chemical analysis of the sediments of the Colorado and of the Nile exhibits wonderful similarity in the constituent parts of each. That of the Colorado exhibiting trihe less potassa, most phosphoric acid and car bonadc of limestone beds through which the Colo rado passes. 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 is superior to artesian waters since it is constantly supplying the land with the richest fertilizng elements. The soil of the valleys is extremely rich in dedomposed vegetable matter and uncombined carbon, readily absorbing the aerial gases such especially, oxygen, which en- tering the soil, decomposes the organic matters that they can be taken up and nOurish the plants which may be considered leading feature in it's fertility. It also readily takes up and retains moisture, while the frmness of it's particles affords every facility for percolation and the activity of capillary action. Inits mechanical composition it's particles in a state of very fine division, which renders it more productive than coarser soils It acqurics heat readily in the daytime, and the loss of the heat at night is very gradual, that it mains always warm and is not subject to sudden changes of heat and cold Besides it's essential stituents of water, organic vegetable matter, sand and clay, a chemical analysis shows that lime, soda, magnesia, iron ammonia and available forms of nitrogen, phosphoric acid and potash enter into composition in the proportions best adapted to add to it's fertility though of course, is always the in soil analysis its composition varies in different localities and is not always constant.
 The soil of the uplands mesas, is lighter and more gravelly and in some places of a free, 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 DOUUO lanuS It never crackS ana reUalS moisture admirably in summer. It is of that character which will produce wine that will keep good for fifty 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 can nowhere be surpassed, containing as it does all the essential elements of richness and fertility.