392 TOBACCO LEAF. 



sened, or prevented, if a half of this quantity of nitrogen is 

 supplied by castor pomace and the other half by nitrate of 

 soda? 



d. What are the comparative effects on quality and quan- 

 tity of leaf of applications of equal quantities of potash in the 

 following forms : Cottonhull ashes, high grade sulphate of 

 potash, the same with lime, double sulphate of potash and 

 magnesia, the same with lime, pure carbonate of potash, and 

 pure nitrate of potash? 



e. Is it possible to absolutely prevent "pole burn" and to 

 cure the crop perfectly on the stalk, by the use, in very damp, 

 "muggy" weather, of artificial heat simply as a means of 

 ventilating and partly drying the air of the barns ? 



The 1896 crop completed the experiments, which 

 have been directed by E. H. Jenkins, vice director of the 

 station. The interest in this work, the most exhaustive 

 of the kind ever attempted, is so great that we have 

 compiled a careful summary of the results. This ap- 

 pears in the annexed table, which is based on the 

 average of the first four crops produced. The quantity 

 of the different fertilizing materials applied per acre 

 each year varied slightly, but averaged for the four years 

 as stated in the table. The same is true of the actual 

 plant food contained in these mixtures. The idea was 

 to supply the same quantity of potash to each plot, but 

 in different form. This was also true of phosphoric 

 acid, but both the amount and form of nitrogen varied 

 considerably. The season of '92 was favorable, and a 

 large yield of fine quality was obtained ; the next three 

 seasons were comparatively dry. The crops, therefore, 

 varied considerably in yield and quality, but the aver- 

 age for the four years partly removes these seasonal 

 influences, and enables us to judge more clearly of the 

 effect of the fertilizers. 



