119 



plot where rlie entire growth of crimson clover was plowed 

 under and smallest on the i)lants growing after oat stubble. 



In one of the experiments described above the yield of 

 sorghum hay after plowing under the entire growth of 

 crimson clover was only 550 pounds greater than after 

 plowing under crimson clover stubble, on land where the 

 yield of crimson clover hay was 2741 pounds per acre. 



In anothei- experiment the superiority of the entii-e 

 growth of crimson clover as a fertilizer over the stubble 

 alon«- was measured by an increase of only 800 pounds per 

 acre 'in the yield of sorghum hay. Here the yield of clover 

 hay <rm the stubble plot was 1441 pounds per acre. Thus 

 both experiments show that it was more profitable to cut 

 the hay than to plow the entire growth under as a ferti- 

 lizer for sorghum. 



Doubtless the princi])al advantage of plowing under the 

 entire growth, rather than the stubble, coisistt". in the 

 greater perma nancy of the improvement in the land. 

 The analysis of the entire plant of crimson clover, includ- 

 ing the roots, and of the stubble alone, (Alabama Station 

 Bulletin No. 00.], showed that only about 10 percent of the 

 total nitrogen was contained in the stubble and roots of 

 crimson clover. With stubble of the usual length, probably 

 20 percent or more of the nitrogen would be found in the 

 stubble and roots. The conclusions suggested by consider- 

 ing together both field tests and analysis are the following: 



(1 I. A greater immediate profit results from using only 

 the stubble as a fertilizer. 



(2). A much larger amount of nitrogen and of vegetable 

 matter is added to the soil by plowing under the entire 

 growth of crimson clover, and hence doubtless this course 

 results in a greater and nioi'^ j»ermanent improvement of 

 the soil. 



(3). By plowing under the entire gTowth a farmer may 

 prepare the bind three or four weeks earlier than by wait- 

 ing to cut the hay, thus making it practicable to grow 

 cotton on a field where the entire growth is plowed under. 



