vines and 2.4(> per cent, of nitrogen in the cow- 

 po«a vines, l)()t]i samples containinii- 1> jxt cent, moisture. 

 The nitrogen in Ihe two stnhl»les was ])ractically equal, 

 1 p<M* rent. 



Let us now considei* tlie results as a whole, combining 

 tliose for the two ])lants and assuming;- that the fcM-tiliz- 

 inu: value of cowpea vines and of velvet Ix^an vine« are 

 (Mpial, and that the stubble of the one plant is as ef- 

 fective as that of the other. Tn what folloAvs the fiijures 

 exi>r(^ss the averaj;e results for cowpeas and v(»lvet 

 b(^ans considered together under the name of summer 

 legumes. 



1x(iii:ase IX THE First Crop After Plowing in the 

 Vines of Summer Legumes. 



With cotton as the first crop the increase in seed cot- 

 ton per acre at Auburn was respectively 367, 546, 696, 

 and 660 pounds of seed cotton per acre. This is an 

 average increase of 567 pounds, worth at 2^ cents 

 (equal to 6f cents for lint, |7.50 per ton for seed) 

 $14.17. 



The yield of seed cotton following the vines of the 

 summer legumes exceeded that on plots where the pre- 

 ceding crop had been cotton to the extent of 32, 64, 83, 

 and 72 per cent. The average increase in the yield of 

 seed cotton attrihutahle to the vines 'of the legumes 

 was 63 per cent. 



With corn as the first crop, the increase per acre at- 

 tributable to plo\nng in the entire growiih of velvet 

 beans was 81 per cent, or 12.3 bushels, worth, at 50 

 cents per bushel, $6.15. 



With oats as the first crop, the effect of the vines of 

 the summer legumes is seen in an increase per acre of 

 10.4, 20.2, and 20.4 bushels respectively. The average 



