The Arizona sentinel., 1896-05-23

of the Gila and Colorado rivers have for the most part a deep sedimeRtary soil of brownish, gray sandy loam resting, in rlost places upon gray clay subsoil at depth of from ten to twenty feet below the surface, The clay subsofl forms hard pan which is mpervious to water. These soils have been slowly formed by the decomposition of shales, sandstones marls. limestones, etc.. mixed with or ganic and vegetable matter, washed down by the mighty rivers and have been gradually deposited during the course of centuries The fertilizing brownish mud held in the wat tlof 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 neven 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 a wonderful similarity in the constituent parts of each. That of the Colorado exhibiting trihe less potassa, most pfrosphoric acid and bonade 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 it is superior to artesian waters since it is constantly supplying the land with the richestfertzing 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 so | that they can be taken up and nouIish the plants which may De considered leading feature in it's | fertility. It also readily takes up and retains moisture, while the frmness of its 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 coarser soils It acquries heat readily in the daytime and the los, of the heat st night is very gradual so that it re mains always 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 lime soda, magnesia, iron, ammonia and available form, of nitrogen, phosphorc acid and potash enter int | composition in the proportions best adapted tC add to it's fertility, though, of course, is alway the case in soil analysis it's composition varies il different localities and is not always constant
 The soil of the uplands, or mesas, lighter anC more gravelly and in some places of a lree, loamy calcareous character. The mesa lands are warm ant generous They seem especially adapted for tn grape, olive and citrus fruits generally. Their soi contains more magnesia, lime or chalk than tn
 bottom lands. It never cracks and retains moistur
 admirably in summer. It is of that character whic
 will produce wine that will keep good for sfty o hundred years, and improve annually, not bein
 liable to souri, or exposure to the air, after on year old, to become turbid and change color in tn
 bottle or glass.
 We can safely say that the soil of Yuma Count
 can nowhere be surpassed containing as it does al the essential elements of richness and fertility.