SULFATE OF AMMONIA. 



91 



Table V. — Average Yield of Soy Beans (Pounds per Acre) 



Weight in green state. 



- Weight dry and ripe. 



Potatoes. — Potatoes have been growai four times, three of them in 

 alternate ye&YS, 1900, 1902 and 1904, in which period the first crop followed 

 clover and the other two followed soy beans. The soil had been limed in 

 1S9S. The seasons were all normal in rainfall. In these three years it is 

 noticeable that the crop steadily diminished j-ear by year on all plots, 

 and in no year was there any appreciable benefit from the sulfate of 

 ammonia; neither can it be said to have injured the crop, as the soil 

 gradually lost the effects of the lime of 1898. It must be considered that 

 either clover or lime had a more positiveh^ favorable result than soy beans 

 or sulfate of ammonia. 



In 1917 potatoes followed millet, which in turn was preceded by clover 

 in t91o. The east half of each plot had been heavily limed in 1913. On 

 the limed areas there was no advantage from the sulfate of ammonia. 

 On the unlimed areas there was a small gain from its use. The unlimed 

 areas had received no lime since 1905, while the limed had been dressed 

 in 1909 as well as in 1913. Under the conditions of this experiment, 

 which are in no case abnormal, sulfate of ammonia was of little benefit 

 to potatoes. 



Table VI. 



Average Yield of Potatoes (Povi^ds per Acre) 



After soy beans. 



3 Lime last applied in 1913 over half area. 



Gi-ass and Clover. ■ — A hay crop consisting largely of clover has been 

 grown in six of the j^ears, but not in any systematic rotation. 



The first crop was red clover in 1899. It had been sown the previous 

 year with oats as a nurse crop, and the land received a dressing of lime 

 over the whole area. The clover was winterkilled somewhat, and was 

 unevenly distributed. There was a sm.all gain on the plots receiving the 

 sulfate of ammonia. 



