244 



THE IRRIGATION AGE. 



often disheartens him; this idea eliminated, the only 

 thought that should dominate his mind, if he con- 

 templates practical success, is, how to abolish the actual 

 differences and arrive at practical uniformity in agri- 

 cultural results. He thinks of the pioneers who went 

 into the forests with their axes and laboriously felled 

 trees and extracted stumps with infinite labor, to pre- 

 pare a clearing, in the soil of which he might plant 

 his sparse crops, and wait years before establishing 

 any sort of home. Perhaps he remembers how a bog 

 or marsh had to be drained, and the years it required 

 to "sweeten" the soil before it could be utilized. He 

 does not fully realize that in the desert his land is ready 

 for his muscles, for his seed, and for his crop ; he does 

 not dream that he does not have to grow old before 

 carving out a comfortable home as he had to do in 

 the old days, back in what he is pleased to call "God's 

 country," and that out in the desert he may have a 

 home and plenty while still young enough to enjoy them. 



The climatic differences -are too much in favor of 

 the desert to desire alteration, but the diametrically op- 

 posite methods of controlling the soil are difficult to 

 be appreciated, though they are never baffling.' They 

 are no greater than elsewhere, but they are opposed bv 

 preconceived opinions, perhaps, rooted prejudices, and 

 are, therefore, apparetly more serious. There are illim- 

 itable treeless regions, covered or patched with stunted 

 vegetation, that receive little or no moisture at all 

 from the clouds, and a soil parched, even burned by 

 the hot sun. Yet the scientists have discovered and 

 classified 197 different species of plants that love the 

 desert soil and nourish in it. Many of them suitable 

 for animal food, all of them indicating sonie quality 

 in or under the soil as plainly as if they were labeled. 



Thus, greasewood, or "creosote bush," indicates less 

 than 0.4 per cent of alkali in the soil ; salt grass and 

 foxtail mean that there is plenty of moisture at the 

 surface of the ground and consequently, the presence 

 of free ground water not far below the surface; shad 

 scale indicates dry land with less than 0.4 per cent 

 of salt: rabbit bush flourishes on sandy soil compar- 

 atively free from salts, and will seldom grow under any 

 other conditions; sweet clover and foxtail indicate wet 

 land and less than four per cent of salts, though sweet 

 clover will grow in six per cent alkali soil and produce 

 a fairly good crop for forage if harvested very early. 



So it is with the color of the soil. Indications are 

 ever present of the dominant characteristics of the 

 ground. Red soils always indicate iron in the form of 

 an oxide; black soils mean carbonate of soda, an alkali 

 ruinous to vegetation; white soils or gray mean soda 

 in sulphate salt form, also deleterious to plants when 

 more than one or two per cent ; gray or brown and black 

 cracked or checked soil with vegetation, signifies adobe, 

 while barren, dark or light colored soil so hard that 

 dynamite is more suitable for its tillage than a plow, 

 is "hardpan," the former indicating a soil retentive of 

 moisture, the latter indicating that moisture is some- 

 where beneath. 



Another peculiarity of desert land soils is the fre- 

 quent occurrence in the soil when plowed or dug up, 

 of innumerable small roots or rooty fibers. They are, 

 indeed, vegetable remains, but through lack of moisture, 

 they have not fermented into humus, though it may 

 be said that they have practically "oxydized" without 

 losing any of their nitrogenous elements. It is well 

 for the desert soil where this organic matter exists, that 

 these rooty fibers have not fermented, for the inorganic 

 matter, the alkalies and other mineral and metallic 



salts would have speedily devoured the product and 

 left nothing for plants to feed upon. The reader has 

 already been informed that both organic and inorganic 

 elements are essential to plant life, and that the inor- 

 ganic elements the substances given in the table in 

 the second chapter and their combinations into salts, 

 are largely in excess of the organic elements. The same 

 principle holds good in the case of desert soils it is 

 not a theory but a practical fact that organic matter 

 added to the inorganic means life ; their separation, 

 death. Hence, it is clear, that the addition or presence 

 of organic matter and nitrogen, added to the mass 

 of inorganic substances in the soil, tempers the latter 

 and lessens its natural tendency to do harm. In the 

 case of an alkali soil, vegetable matter and nitrogenous 

 substances lessen the deleterious effects of the alkali, 

 although it may not reduce the percentage of the salts. 

 Whence, also, the presence of masses of coarse or fine 

 vegetable fibers in the soil is evidence of either the 

 absence of an excess of alkali, or that it is under con- 

 trol and inocuous to vegetation. Perhaps the reader 

 may see in this a way to get rid of the alkali in soils 

 and render them fertile. If he does, he will not be 

 far wrong in his idea, as we shall see presently. 



LACK OF WATEU. 



There are two conditions which are the bane of 

 all desert lands, whether arid or semi-arid : Lack of 

 water and the presence, in excess, of alkalis. We shall 

 devote space here to some general remarks on both 

 conditions, leaving it to subsequent chapters to enter 

 more into details. The chapters on "Alkali Soils," 

 "The Relations of Water to the Soil," and that on "Cul- 

 tivation," will give more particulars, though at this 

 point it may be necessary to include matter which will 

 be repeated elsewhere, or presented from a different 

 viewpoint. This, however, should not be deprecated 

 as a fault, but extolled as a benefit, for the subject is 

 of so much vital importance that it can not be repeated 

 too often, lest it be forgotten. 



There must be a water table at some point below 

 every soil, at a less or greater depth. This may be 

 accepted as a fact without going into geology to prove 

 it. Such subsoil water originates in a variety of sources, 

 through percolations from above, underground streams 

 coming from great distances, from springs that have 

 their original sources in some nearby hill or mountain 

 land, by seepage from rivers, brooks, or streams, from an 

 irrigating ditch, or pond, and from the artificial sur- 

 face application, or through sub-irrigation. Although 

 the action of the earth's gravity pulls or draws water 

 downward as it does every other object heavier than 

 the atmosphere, the constant natural tendency of the 

 water beneath the surface is to rise to the surface and 

 evaporate. 



It is this rise of the water table to the surface 

 that causes more alarm than any other process of nature 

 in the arid and semi-arid regions, particularly in the 

 arid regions where all water must be applied artificially. 

 The reason is obvious. The subsoil water contains in 

 solution whatever soluble salts it may come in contact 

 with, and reaching the surface, evaporates, leaving be- 

 hind a deposit of the salts as crystals. Constant deep 

 cultivation also has a tendency to bring up the water 

 table with alkaline solutions, for we have already seen 

 that the subsoil contains in reserve as much mineral 

 matter and salts as the surface soil. And this is so- 

 whether the land is in the arid regions or in the rain 

 belt, the disadvantage of the desert land being that the 



