New Youk AGnicuLTURAL Experiment Station. 



353 



TABLlE XI. COMrABATIVE YIELDS IN DRIED BLOOD SERIES WITHOUT 



Manure and With Different PRoroRTioNS of Manure, 



CLAY LOAM. 



Comparative yields with— 



' With the manure used, 5, 10, 15 and 20 per ct , by weight are equivalent to 11 J, 22J, 34 and 

 45J per ct., respectively, by bulk. 



■■' All plants under these hendiufrs received 600 pounds acid phosphate per acre, 400 pounds sul- 

 phate of potash and 1,000 pounds dried blood, except where 33J per ct. of manure was used. 



3 This is equivalent to 14 2 per ct by weight for flrst crop on the cl.iy loam and 14.7 per ct. 

 for the first crop on sandy loam. No commercial fertilizers were used on these boxes. 



Leaving out of consideration for the present those portions 

 of soil which received 33 1-3 per ct. of manure without any com- 

 mercial fertilizers, let us compare the rate of increase of the 

 yield where none but commercial fertilizers were used with the 

 rate where these were combined with manure. 



From the table just given it appears that on the clay loam the 

 use of 5 per ct. for the first crop gave an increase of 10.19 points 

 over the yield with no luanure; doubling the manure gave a 

 23 



