154 One Thousand Questions in Agriculture 



It is not unusual to find people who predict the rise of alkali 

 almost anywhere except on their own premises. No one can exactly 

 tell where alkali will go, because no one has complete knowledge 

 of the water movement in underlying strata. Wherever the ground 

 water rises on lower levels because of irrigation on higher levels 

 there is danger of the rising of the alkali, for which the only cure 

 is underdrainage with tile so that this rising water is carried to an 

 outflow and not allowed to approach within three or four feet of 

 the surface. If you have such an outflow and desire to undertake 

 the expense of tiling, you can insure yourself against a serious rise 

 of alkali indefinitely. We do not see, however, how alkali can rise 

 to the higher lands of the valley. Its first effect would be to make 

 lakes or ponds in the lowest parts of the valley, and even then the 

 surrounding mesa lands would not be injured. 



Plants Will Tell About Alkali. 



Please give information as to the application of gypsum to my soil 

 which is somezvhat alkaline. I do not care to have an analysis made of 

 my soil, and believe that you can advise me zuithout it. 



If your soil is too alkaline for the growth of plants you can 

 demonstrate that fact by experiment, or if it is capable of being used 

 by the application of gypsum, that also can be determined by ex- 

 periment and noting the behavior of the same plants afterwards. 

 It is rather a slow process but it is sure enough. 



Litmus and Alkali. 



Is there any simple soil test for alkali that can be made zvithout a 

 chemical analysis? 



You can ascertain the presence of alkali by using red litmus 

 paper, which will be turned blue by the alkali in the soil, if the soil 

 is moist enough. This does not determine the amount of alkali, but 

 the quickness of the turning to the blue color and the depth of the 

 color are both attained when the alkali is very strong. When there 

 is less alkali, the reaction is slower and weaker. This test, however, 

 gives you only a rough idea whether the soil is suitable for growing 

 plants. You can tell that better by the appearance of the plants 

 which you find. Any druggist can furnish the litmus paper, and give 

 you a demonstration of how it acts on contact with alkali. 



Using Gypsum for Alkali. 



Is it better, to kill the black alkali in the soil zvith gypsum, just to 

 scatter it over an alkalied spot or to plozv the soil iirst and then use the 

 gypsum? I am going to sozv alfalfa. 



Use the gypsum after plowing, for it will wet down more 

 quickly, and the gypsum has to be dissolved to act freely. The best 

 way to cure your spot is to run an underdrain into it, if possible, 

 so the rain-water can run through the soil freely and take the alkali 

 with it. 



