175 



ranged from 24 to 54 per cent. The effect exerted by the 

 vines of the legumes on the third succeeding crop was 

 tested in only one field, the increase in oats as the third 

 crop after cowpea vines being 3.2 bushels per acre, or 

 14 per cent. With sorghum planted in 1901 as the 

 fourth crop immediately after the oats were cut, there 

 was a perceptible increase on the plots where the vines 

 of cowpeas and velvet beans grown in 1898 had been 

 plowed under; extremely unfavorable conditions and 

 partial failure of late sorghum detract from the relia- 

 bility of the percentage figures for this, the fourth crop. 

 For three years or four crops the large mass of vines 

 continued to exert some influence. This experiment was 

 conducted on a soil of the stiffest type found on the 

 station farm, which, however, is fairly permeable to 

 water, and which might be described as a reddish loam 

 containing an abundance of large flint stones. 



\\e should expect an equal ma-ss of leguminous vege- 

 tation employed as fertilizer on clay or prairie soils to 

 exercise a favorable influence for at least three years,''-, 

 or probably for as long a period as do heavy applica- 

 tions of coarse stable manure. Local experiments to 

 determine the permanency of the action of the legume« 

 are greatly needed, and correspondence is invited from 

 parties wishing to make such tests. 



It is our expectation to continue work along the lines 

 indicated in this bulletin, and it is highly desirable that 

 these investigations should be extended to include soils 

 of a character different from that at Auburn, though 

 the means of doing this in a thorousfhlv satisfactorv 

 manner are not now in sight. 



In conclusion the writer would reaffirm his previous 

 statement, made in Bulletin Xo. 107 of this station, as 

 follows : 



