16 BULLETIN 1094, TJ. S. DEPARTMENT OF AGRICULTTJEE. 



barley from the rye rotation. It is doubtful whether the differences 

 are significant. 



The corn in these five rotations has made only three good crops. 

 Some of the losses have been from grasshoppers and chinch bugs. 

 These concentrate on the plats from the grain fields by which they are 

 surrounded and sometimes cause losses which large fields would not 

 suffer. To that extent the average may not be equal to the average 

 that com may attain in the section. But some of the losses have 

 been from drought and hot winds, which are no more serious on plats 

 than on larger fields. 



The two rotations containing kafir have made average yields of 

 18.3 bushels of kafir grain and 4,648 pounds of stover iu rotation 

 No. 55, containing rye for green manure; and 20.3 bushels of grain and 

 4,698 pounds of stover in rotation No. 56, containing peas for green 

 manure. Barley following the kafir has averaged 17.5 bushels in 

 rotation No. 55 and 19.2 bushels in rotation No. 56. These yields of 

 barley following kafir compare favorably with those following corn 

 and are very nearly equal to the yields of barley following imme- 

 diately after green manure. Barley in alternation with fallow on 

 plats not, previously introduced into this discussion has averaged 23 

 bushels per acre for the same period of years. The wheat in the rye 

 rotation has averaged 16.5 bushels and in the pea rotation 15.5 

 bushels. These rotations clearly show the superiority of kafir over 

 corn in the production of both grain and stover. The other crops in 

 the rotations show no disadvantage from the kafir in them. Unfor- 

 tunately there is not in this block any winter wheat immediately fol- 

 lowing kafir. The extent of work that could be started originally 

 was limited, and the general experience and belief that wheat did not 

 follow the sorghum crops successfully was accepted as sufficient rea- 

 son for not including this method. 



Two other rotations in this block introduce sod crops. Rotation 

 No. 141 is oats on brome-grass sod, com on spring-plowed oat stubble, 

 winter wheat on disked corn ground, and three years of brome-grass. 

 For several years the grass seed was so^vn in the winter wheat in the 

 spring, but a stand was never obtained in this way. After failure to 

 obtain a stand by this method the wheat stubble was plowed in the 

 fall and the brome-grass seeded in the spring. Better results attended 

 this method, but it is not always possible to get a stand and bring it 

 through the summer. The rotation has been a failure as far as the 

 grass crop is concerned. The only hay harvested was in 1916, 1919, 

 and 1920. About haK the time there has been a fair sod to break for 

 oats. Breaking has been done in summer at the time of fall plowing. 

 Oats have averaged 20 bushels per acre in this rotation, which is 

 about the same as the average following grain crops, but in the 

 years when a heavy sod has been broken the yield has been low. 



