The Arizona sentinel., 1898-10-15
LANDS AND SOILS.

Ihe lands ot Yuma County comprise the river bottoms and valleys and the uplands or rnosas Tho bottom ands are moister and slightly mere fertile It, indeed, it is possible to make comparisons where all are wonderfully productive and prolific me upands or mesas are warmer and, perhaps,
 lightly for betterthe cultivation of the citrus fruits Yuma contains variety of soil The valley land or thei Gia and Colorado rivers have for the most part deep sedimentary soil of brownish, gray San1y loam resting, in most places, upon a crav claJ 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 shaIes sandstones, marls. limestones, etc, mixed with or g1nle and vegetable matter, washed down by the mighty rivers and have been gradually deposited during the course of centuries. The fertilizing orownlsh mud held in the wat tIof the Colorado and Glla rivers resembles that from the Nile. and Its quantity varies from O.1 to O.5 per cent. though the water hen even considerably discolor- ed by mud is good drink, resembling in this res PecG the Missouri river water. 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 exhIbitipc a trl1e less potaSsa, most phosphoric acid and car Donade 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 used for irrigation it is superior to artesian waters since It IS constantly supplying the land with the rchestIerGlAzIng elements. The soil of the valleys Is extremely rich in dedompOsed vegetable matter ana uncombined carbon, readily absorbing the aerIal gases, such especially, as oxygen which en- terlng the soil decomposes the organic matters so that they can be taken up and nourish the plants "liIcli may De considered a leading feature in It Ieftlhty. 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. In its mechanical co1opositon it's particles are ill state of very fine division which rehderS It more productive than coarser soils I acqulries heat readily in the daytime, and the loss or 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- stltuents of water, organic or vegetable matter sand and clay, 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 as is alwa,s the case in soil analysis, its composition varies ill d'herent localities and is not always constant.
 The sof the uplands, or mesas, lighter and more grayeliy and in some places of .ree, loamy, calc2reous 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 chalk than the bottom lands It never cracks and retains moisture admlrabIy III 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, or exposure to the air after one year old, to become turbid and change color in the bottle or glass