496 Journal of Agricultural Research voi. \^, no. 13 



The results from the cowpeas show some points of particular interest. 

 There was scarcely any seed produced for the pots to which 1 1 and 22 gm. 

 of raw rock had been applied, but there was a decided increase for the 

 pots which received 66-gm. applications. The next treatment, which 

 was 220 gm. per pot, showed a slight increase, approximately 3 bushels 

 per acre. For the cowpea hay the results are very similar to the seed 

 yield. There is not a very marked increase in the hay production until 

 the larger applications are made. The pots which received 66 gm. 

 produced nearly as much hay as the pots which received 22c^gm. of rock 

 phosphate. 



Cowpeas do not give results that correspond with those from soy- 

 beans. In the first place, the no-treatment pots produced a significant 

 quantity of soy-bean seed, the yield on the acre basis amounting to 2.64 

 bushels, while the returns from the pots receiving the largest applica- 

 tion just about quadrupled those from the former. The ratios for the 

 yields of hay are about the same as for the grain. The yields for both 

 seed and hay in the case of soybeans are unsatisfactory, which is not 

 true of the cowpeas. It would seem that the latter legume utilizes rock 

 phosphate better than soybeans. 



To the practical agriculturist the returns from red clover will prove of 

 considerable interest. It will be observed that the lowest treatment, 1 1 

 gm. per pot, produced hay at the rate of 772 pounds per acre. With 

 double the application a little less than the former yield is recorded. 

 When the lowest application is increased to six times the original amount, 

 the yield of hay is increased about three times. The largest application, 

 which was 20 times that of the lowest, produced practically 10 times as 

 much hay as the first treatment. The above figures are for the first 

 cutting only. 



For the second harvest the relative yields of the 22- and 66-gm. treat- 

 ments are more satisfactory than for the first cutting. It will be observed 

 that the yield of the pots with 11 -gm. applications and those with the 

 220-gm. applications hold the same relation for the second cutting as for 

 the first. No direct comparison for the third cutting should be made, 

 because pot 79, just previous to cutting, was attacked during a single 

 night by a large cutworm which did considerable damage to the growing 

 crop. It is true, however, thai there had not been as much difference 

 in the growth on the high-treatment pot as had been observed earlier in 

 the season. The total yield for three cuttings for the heaviest application 

 is large, but it can hardly be said that the pots which received 22 gm. 

 of rock phosphate produced unprofitable yields. 



Because of its extensive root system alfalfa would be expected to 

 produce greater yields than clover. However, the difference in this 

 experiment is not so marked. From four cuttings of alfalfa the yield of 

 hay from the lowest treatment was 5,451 pounds, as against 1,819 pounds 



