32 BOAED OF AGRICULTURE. [Pub. Doc. 



high-grade sulphate of potash, the same with lime, double 

 sulphate of potash and magnesia, commonly called "low- 

 grade" sulphate, and the same with lime. 



The plots that had ashes were supplied with 150 pounds 

 of phosphoric acid per acre, in the ashes themselves, so to 

 the other plots we added this quantity of phosphoric acid in 

 form of Cooper's bone dust, to make the conditions as nearly 

 even as we could. Averaging the results of five years to- 

 gether, good seasons and bad, we find that the plots dressed 

 with ashes and other forms of carbonate yielded less tobacco 

 yearly by 100 to 150 pounds than those dressed with some 

 form of sulphate of potash. 



But in general quality of leaf the tobacco dressed with 

 carbonates was considerably better than that dressed with 

 sulphates. The tobacco raised on the double carbonate of 

 potash and magnesia was the best we raised ; that on wood 

 ashes came next. It was noticed that, as a rule, the tobacco 

 raised on the sulphates did not have as good a burn nor 

 hold fire quite as long as that raised with the carbonates. 



These experiments in the application of fertilizers to 

 tobacco have been carried out for five years with all the care 

 and skill at our command. Certain questions regarding the 

 effects of a number of fertilizer materials, which have been 

 vainly discussed for a long time, have been answered by 

 these experiments as completely and definitely as is in the 

 nature of things possible. 



One fact, emphasized by our experience, is that there is 

 no " best " tobacco fertilizer or " best" formula for all sea- 

 sons, even on the same soil. A formula or a form of plant 

 food which in one season gives to the leaf a somewhat better 

 quality than any other, may, perhaps, the next year and on 

 the same soil prove inferior to others, for reasons which can 

 only be surmised. Nevertheless, by comparing the effects 

 of these fertilizers for a term of years, it appears that cer- 

 tain ones are, on the whole and generally speaking, more 

 likely to impart a perfectly satisfactory quality to the leaf 

 than certain others. 



The opinions of growers regarding tobacco fertilizers are 

 widely divergent, and the prejudices of both growers and 

 dealers are sometimes strong. Thus, certain growers de- 



