manure that the poor soil responds to a much greater degree than the 

 good one, the maximum increase attributable to manure being about 

 75 per cent. As a result of many experiments with these two sam- 

 ples of soil where manure has entered into the treatment in amounts 

 ranging from 2 to 20 tons per acre it has been found that the small 

 amounts give relatively larger increases than the larger amounts, 

 and it suggests the probability that applications of barnyard manure 

 in field practice will be most economical if applied at the rate of 

 about 10 tons per acre. 



EFFECT OF LIME. 



Lime having proven decidedly beneficial, especially on the poor 

 soil, it was applied in different amounts ranging from 1,000 to 

 8,000 pounds per acre, the rate of application being based on the cal- 

 culated weight of an acre of soil to a depth of 7 inches, w r hich is 

 approximately 2,000,000 pounds. The following table shows the rela- 

 tive increase in growth attributable to the different applications of 

 lime as compared with the untreated soil, which is taken as 100 in 

 each case: 



Effect of lime on Lconardtown loam. 



The lime above used was air slaked. It will be noticed that its 

 effect is relatively much greater on the poor soil than it is on the good 

 one, and that there seems to be no appreciable increase for applica- 

 tions greater than 1,000 pounds per acre. In other words, the lime 

 requirements of the soil seem to be fully met by applications of 1,000 

 pounds, but there is apparently no harmful effect even where the 

 amount is 8,000 pounds per acre. It is possible that in subsequent 

 'rops the larger amounts may have a residual effect greater than the 

 smaller application, but it would seem wiser to give small applica- 

 tions at frequent intervals rather than large applications with the 

 expectation to have the results extend over a long period of time. 

 In another experiment where lime was applied at the rate of 6,000 

 pounds per acre and three successive crops grown without re-treat- 

 ment, the yield for lime was 130, 213, and 112 for the first, second, 

 and third crops, respectively, as compared with 100 for each of the 

 three successive crops grown on the untreated soil, or a mean gain 



