The Arizona sentinel., 1898-12-24
LANDS AND SOILS,

Inc lands Of Yuma County comprise the river bottoms and valleys and the uplands or mcsas The bottom ands are moister and slightly mere fertile If, indeed, it is possible to make comparisons where all are wonderfully productive and prolific The uplands mesas are warmer and, perhaps lightly for better the cultivation of the citrus fruts Yuma contains a variety of soil The valley land of thel Gila and Colorado rivers have for the most part deep sedimentary soil of brownish, gray san1y loam, 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. imestones, etc., mixed with or ganic and vegetable matter, washed down bv the mighty rivers and have been gradually deposited during the course of centuries The fertilizins brownish mud held in the wat tIof the Colorado and Gila rivers resembles that from the Nile. and its quantity varies from O.1 to O5 per cent. though the water " hen even considerably dscolor- ed by mud is good drink, resembling in this res 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 a trihe less potassa, most phosphoric acid and car bonade of limestone beds through which the Colo rado passes. In other respects the sediment of the Colorado is almost identical with tha 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 rlchesttertiizing elements. The 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, decomposes the organic matters so that they can be taken up and nourish the plants Wnlcn may 0e considered leading feature in 1t fertility. It also readily takes up and retains moisture, while the rmness of it's particles affords every facility for percolation and the activity of capillary action. In ts mechanical composition it's particles are in state of very fine division which renders it more productive than eoarser soils I acquires heat readily in the daytime and the loss of the heat at night is very gradual so that it re- mains always warm and Is not subject to sudden changes of heat and cold Besides it's essential con- stituents of water, organic or vegetable matter, sand and clay, chemical analysis shows that lin,e 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, as is always the case in soil analysis, it's composition varies in different localities and is not always constant.
 The sol the uplands, or mesas lighter and more gravely and in some places of lree, Ioamy, 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 CT 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 good for fifty or hundred years, and improve annually, not being liable to sour, exposure to the air, after one year old, to become turbd and change color in the bottle or glass.