OKLAHOMA ACADEMY OF SCIENCE 59 



TABLE 6. 



1917 1921 



Check Plots (Average) 43.59 Bushels 30.62 Bushels 



Manure 55.94 Bushels 34.06 Bushels 



Residues 51.56 Bushels 31.56 Bushels 



Check Plots (Average) 33.75 Bushels 44.99 Bushels 



Manure 33.75 Bushels 50.00 Bushels 



Residues 27.81 Bushels 42.18 Bushels 



This table shows that the rotation check plots averaged 9.84 

 bushels per acre lower in yield at the beginning than did the con- 

 tinuous check pl(jts. At the end of 1921 or five years cropping, 

 they were yielding 14.37 bushels per acre more grain than the con- 

 tinuous check plots were at the same time. Theoretically if the 

 plots had had the same average at the beginning (1917) and had 

 behaved in the same ratio in which they have, the yields of oats 

 on the rotation check plots in 1921 would have been 24.21 bushels 

 per acre above the yields obtained on the continuous check plots. 

 In practice, however, w^e are aware that the difference would not 

 have been so great because with a poorer soil to start with the 

 decline irf yields would not have been in the same ratio. 



The money value for the oat crops is shown in Table 7. The 

 price per bushel used in the calculations is fifty-three cents which 

 is the average farm price paid for oats in Oklahoma for the. ten 

 years 1911-1920. Columns 5 and 6 of Table 7 show the value after 

 the cost of tlie extra threshing and hauling to market due to in- 

 creased yields are deducted. Eight and one-half cents per bushel 

 was allowed for the threshing and five cents per bushel was allowed 

 for hauling. Other minor expenses were not considered. 

 Table 7 Continuous Oats _ 



Value after cost 

 of extra thresh- 

 ing and hauling 

 is deducted 



