Lysimeter Experiments 49 



to be a tendency for this peculiarity to disappear as the period after 

 Hming lengthens. 



Sufficiency of the lime application 



The four feet of soil in these tanks contains calcium at the rate of about 

 83,631 pounds per acre. The annual loss from the planted tanks, when 

 calculated for both crops and leachings, is 194.2 pounds per acre, and 

 from the unplanted tanks it is 367.4 pounds At this rate the annual 

 loss amounts to 0.23 per cent of the total in the planted soil and 0.44 

 per cent in the unplanted soil. At the present actual loss per acre the 

 planted soil would become exhausted of its calcium in 430 years and the 

 unplanted in 228 years. Such a statement, however, signifies nothing, 

 as the actual annual loss would decrease with the quantity of calcium 

 present in the soil and thus the date of exhaustion would be delayed 

 greatly. On the other hand, the soil would probably become unfit for 

 ordinary farming long before the shorter of these periods had been 



passed. 



The data obtained doubtless have some practical bearing on the quantity 

 of lime that it will be necessary to add to such a soil in order to keep it 

 up to its present content of calcium. This for the planted soil would 

 amount to 271 pounds per acre annually, and for the unplanted soil 514 

 pounds. 



It appears from the results obtained that the quantity of lime applied 

 in 1910 was not sufficient to greatly benefit the soil. No increased yields 

 of non-leguminous plants were obtained as the result of liming, but clover 

 responded to the application. This indicates some benefit, altho not all 

 that might have been expected from an adequate application. The 

 failure of the limed soil to form more nitrates than the unlimed soil is 

 another indication of the insufficiency of the application. 



removal of magnesium 



Magnesium was found in much smaller quantity than was calcium, 

 both in the drainage water and in the ash of the crops raised. The average 

 amount of magnesium removed annually from the soil by drainage water 

 and by crops during the five-years period is shown in table 31: 



4 49 



