12G 



G.C) Imslicls of corn \h^v acre, or 40 per cent. 



.5 Urn ui" feurghuui hay, ur per cent. 



452 pounds of seed cotton jut acre, or. . . .40 per cent. 



With these three crojK^ tli(» avera.i^e increase in value 

 l)er acre was $5.1)8 gr(*ater from vines than from stubble. 

 ^\'illl oat^; and wheat tlie vini^ of these sununer le<;umes 

 were not superior to the stubble when the small j.?rains 

 were sown immediately after the legumes matured. 



The fertilizing etTect of the stubble of cowpeas or 

 v(4vet beans was very transitory on sandy land, the aver- 

 age increase in the second crop of corn after the stubble 

 being only 1.34 bushels per acre, or 12 per cent., as 

 compared with the yield of a plot that had not borne 

 legumes. • 



The fertilizing effect of the vines of cowpeas and 

 velvet beans was less transitory than that of the stubble, 

 and the increase was 24 to 54 per cent, in the second 

 crop, 14 per cent, in the third crop (oats), and the favor- 

 able effect was even perceptible in the fourth crop 

 (sorghum) grown in the same year as the third. The 

 total increase in value of the four crops occupying cer- 

 tain plots during the three years after the plowing un- 

 der of the vines of cowpeas and velvet beans was $42.97 

 per acre, an annual increase of |14.32 per acre. 



On the other hand, on very light soil the fertilizing ef- 

 fects of both stubble and vines had practically disap- 

 peared within twelve months after the plowing in of the 

 legumes. 



Corn as the second crop yielded 14 per cent., or 2.1 

 bushels more after legume vines than after legume stub- 

 ble, this representing a value of f 1.05. The permanency 

 of effect of legumes in eoil improvement seems to be in 

 proportion to the stiffness of the soil and to the mass of 

 vegetable matter afforded by the legume, and the favor- 

 able influence of leguminous yines is apparently not 

 less permanent than that of stable manure. 



