171 



soil-improving plants, instead of non-leguminous plants, dur- 

 ing the preceding season. 



Undoubtedly this is an extreme, and not an average, case. 

 If cottonseed meal, or other nitrogenous fertilizer, had been 

 used on all the plots of oats, the plants on plots 2 and 5 

 would have made much better growth, and the difference in 

 favor of the leguminous plants would have been reduced. 



A gain of five to fifteen bushels of oats per acre as a re- 

 sult of plowing under cowpea stubble or vines would make 

 the growing of cowpeas for fertilizer a profitable operation, 

 and it is far safer to count on such an increase as that obtained 

 in our first experiment, (10.4 bushels), rather than to expect 

 such an exceptional increase as that obtained in this last ex- 

 periment. 



An unexpected result of this experiment is the larger 

 crop on the plots where only the stubble was left than on those 

 where the vines of cowpeas and velvet beans were plowed 

 under. The plots were of nearly uniform fertility, as judged 

 by the location and by the uniform growth of cotton on all 

 plots in 1896. While admitting the possibility that the two 

 west plots (plots 3 and 6) were slightly richer than the two on 

 the east (plots 1 and 4), the writer thinks that the difference 

 in yield was almost wholly due (1) to the fact that the vines 

 (especially those of the velvet beans) were not properly buried 

 by the small plow employed, and (-2) that the seed bed for oats 

 was more compact where only stubble was plowed under, a point 

 of advantage, doubtless, in such a dry winter as that of 1897-98. 

 It does not follow that the land will be permanently 

 benefited by a cowpea stubble to a greater extent than by 

 cowpea vines. The reverse is probably true. The effect of 

 both stubble and vines on late corn, following oats, is now be- 

 ing determined. It is usually more profitable, where many 

 head of live stock are kept, to save the cowpea hay and plow 

 under only the stubble than to pick the peas and plow under 



the vines. 



Time of Applying Nitrate of Soda. 



Nitrate of soda is valuable for its nitrogen, of which it 

 contains about 16 per cent. Nitrogen in this form usually 



