BULLETIN 4 E. 



Increase in yield due to fertilization. 



These results show that, both relatively and absolutely, add- 

 ing fertilizers to the poorer soils has had a greater effect than 

 the same treatment with stronger soils. The guano added was 

 the same on all soils but the presumption is that the stronger 

 soils received a better quality of manure than the poorer soils 

 did, from which it follows that the fertilizers have had a lower 

 efficiency on the stronger soils. 



It was not practicable to determine the per cent, of water in 

 the corn at the time it was cut, as should have been done for 

 strict comparison of yields. It is probable that 33% per cent, 

 of dry matter is too low, but may be taken as a safe estimate. 

 On this basis, the mean yields of dry matter will stand as be- 

 low. 



Estimated increase in yield of dry matter in corn due to fertiliza- 

 tion. 



