THE IRRIGATION AGE. 



177 



excessive amounts, they prevent the 

 plants from taking up their needed food 



and water supply. " 



******* 



'One of the most discouraging features 

 of the whole problem is that the owner of 

 a tract of land may use the most approved 

 methods of irrigation, and yet be com- 

 pletely ruined by the excessive and inju- 

 dicious use of water by his neighbor, who 

 may himself escape the injurious effects of 

 his own crude methods, at least many 

 years after his neighbor has been 

 ruined." * * * * 



Summing up the investigations and 

 conclusions of the authors we get the 

 following: 



'The results of these investigations 

 show that the ultimate source of the al- 

 kali is in the sandstone, and particularly 

 in the shale or slate rocks from which the 

 soils have been derived. Before irriga- 

 tion was introduced the salts were pres- 

 ent in rather large amounts, but well dis- 

 tributed throughout the soil, and not in 

 such large quantities as to be injurious to 

 crops. The injury is due entirely to over- 

 irrigation, to the translocation and local 

 accumulation of salts by means of seepage 

 waters, and to the imperfect drainage 

 facilities in the compact gumbo soils and 

 the inability of the soils to remove the ex- 

 cess of salts and of seepage waters. The 

 first trouble appears to be due to the 

 seepage waters. This, of course, need 

 not necessarily be so, but it appears to be 

 the case in this locality. The open sandy 

 lands, having better nnderdrainage, are 

 not likely to be injured by a rise of salts 

 except from an excessive application of 

 water or in the low places in the path of 

 the drainage system, especially when these 

 are underlaid, as they are liable to be. by 

 the heavy gumbo subsoils. The gumbo 

 soil requires great care in cultivation, as 

 it is easily ruined by the accumulation of 

 seepage waters and the subsequent accu- 

 mulation of salts." 



"Where the damage has been done, or 

 where the conditions are so imminent that 



ultimate ruin can be forseen. the logical 

 method of reclamation is in providing ade- 

 quate systems of drainage to carry off the 

 excess of water and the accumulated salts. 

 This is expensive, but it is the only thing 

 in this case to hasten the slow processes of 

 nature, which are entirely inadequate in 

 the presence of the present methods of ir- 

 rigation and of. culture. Underdrainage 

 is expensive, but it has amply repaid for 

 the investment in other localities where 

 land is worth no more than in the Yellow- 

 stone Valley. Any land which is worth 

 s50 per acre could well afford to be taxed 

 for underdrainage if it is necessary, as in 

 many places in the Yellowstone Valley, 

 to save the investment from utter anni- 

 hilation." 



"It must not be assumed, ho wever.that a 

 thorough system of underdrainage relieves 

 one from exercising care and judgment in 

 applying water to the land. There is less 

 immediate danger of ruining the land, 

 to be sure, but there are two things to be 

 considered, namely, that an excessive use 

 of water means just so much loss to irri- 

 gation and so much less land which can 

 be brought under the ditch, and also that 

 in the removal of these salts by the flow 

 of the. seepage waters out through the 

 drainage system large quantities of really 

 valuable plant food are likely to be re- 

 moved from the soil. The very accumu- 

 lation of these soluble salts is due to the 

 arid conditions of the climate. The great 

 fertility of the soils results from the accu- 

 mulation of these salts, and if we intro- 

 duce artificial drainage, which will tax 

 the resources of the soil, we may remove 

 in the course of a generation, or even in 

 less time than this, the accumulated re- 

 sults of the changes of vast geologic ages 

 in the disintegration of rocks. By over- 

 irrigation and underdrainage we may re- 

 move in a few years the very conditions 

 which contribute to the wealth of the 

 country in the fertility of the soil. " 



"Great care must be taken in the appli- 

 cation of water. As little as possible 

 should be applied at each time, so that 



