158 ALFALFA 



Correcting Acid Soils for Alfalfa. -- The natural home for 

 alfalfa is on limestone soils or other soils that are well sup- 

 plied with lime. No matter how favorable other conditions 

 may be, if the soil is sour, it will be necessary to neutralize 

 the acidity before it will be possible to obtain good 

 results. 



Acid land can occasionally be detected by plants such as 

 sheep sorrel, horsetails, and mosses that thrive on it. 

 It can always be determined by testing it with blue litmus 

 paper in the following manner. Take some moist earth 

 from a few inches beneath the surface of the ground and 

 press it firmly over a strip of blue litmus paper. Do not 

 handle the litmus paper when the hands are moist as the 

 perspiration from them may cause the paper to show an 

 acid reaction when no acid is present in the soil. After 

 the paper has remained in the soil for ten or fifteen minutes, 

 the litmus will change in color from a blue to a pink or red, 

 if the soil is acid. This acidity must be corrected before 

 alfalfa can be grown to advantage. 



Acidity can be corrected either through the application 

 of pulverized limestone, dry marl, or slaked lime. The 

 best results seem to be obtained by the use of limestone or 

 marl. No evil results follow their use as is occasionally 

 the case with caustic lime. Over an acre of ground there 

 should be scattered two to three tons of pulverized raw 

 limestone or one to two tons of marl. Heavy applications 

 of barnyard manure seem to benefit most acid soil suffi- 

 ciently to get a catch of alfalfa. After alfalfa has become 

 well established on land high in fertility it seems to thrive 

 even on acid soils. The application of lime has a beneficial 

 effect on leguminous plants other than merely correcting 

 the acidity of the soil. 





