Further Experiments on the Economic Value of Root Crops 555 



It is noticeable that the best yield reported was obtained at the highest 

 cost per acre, but not at the highest cost per ton. A fairly good yield at 

 a moderate cost made a low cost per ton in one of the experiments. The 

 average yield for the eight trials was not much higher than the average 

 yield of root forage reported in the census. The average cost of a ton of 

 mangels, after allowing an additional $5 for land rent and $4 for seed to 

 sow an acre, seems to be within the cost limit set in Bulletin 268 for the 

 economical production of roots to be used as a substitute for half of the 

 grain ration in feeding dairy cows. 



In iQio further cooperative experiments were tried with a small number 

 of farmers. One variety of mangels, the Long Red, was used. With it 

 were grown a plat of corn for silage, a plat of soy beans and corn, and a 

 plat of sunflowers and corn. The varieties of com used were not pre- 

 scribed and different varieties were chosen. The cost of labor and fer- 

 tilizers was kept for both mangels and corn. Four experimenters reported 

 results of a character allowing of comparisons. Their results are shown 

 in Table 6 : 



TABLE 6. Cooperative Experiments in 1910 with Corn and Mangels 



The cost of com production was very moderate for eastern conditions. 

 The yields were normal and creditable. The best crop of mangels was 

 grown at the mean cost per acre for all four trials. The significant result 

 was that, while the mangels yielded more tons per acre than did the com, 

 and the cost per ton was one third less than in the other cooperative ex- 

 periments, yet the acre cost and the ton cost of corn-growing was prac- 

 tically one half that of mangel production. The number of experiments 

 was not large enough to make the results conclusive, but since none of 



