BuEEAu OP Agbioultxtbe. 165 



quantities furnishing the same amount of nitrogen as 

 in 100 lbs. of nitrate of soda. The experiments were run 

 in duplicate. On account of the excessive drouth the 

 tobacco was almost a complete failure, the crop from two 

 acres being sold for fifteen dollars. The tobacco did 

 not use the nitrogen. The ground was seeded to rye on 

 one of the series of plots and to wheat on the duplicate 

 series. There- was no sign of any effect of the nitrogen 

 on the wheat or the rye either in the fall or spring. This 

 soil is decidedly deficient in nitrogen. 



However, we frequently recommend the use of ni- 

 trate of soda or sulphate of ammonia as a spring top- 

 dressing for wheat on soils deficient in nitrogen provided 

 there is a sufficient supply of phosphorus in the soil 

 either naturally or by application. On the average Ken- 

 tucky soils outside the highly phosphatic Blue Grass belt 

 we would not recommend the use of nitrate of soda or 

 sulphate of ammonia on wheat land that had not been 

 treated with phosphate, because nitrogen cannot increase 

 the yield when phosphorus is a limiting element. The 

 use of nitrogen in this way contributes nothing to the im- 

 provement of the soil. 



Dr. A. M. Peter has been running an experiment on 

 tobacco on the Experiment Station farm at Lexington 

 in which one plot is fertilized with a complete fertilizer 

 and the other with nitrogen and phosphorus. It is con- 

 tinuous culture of tobacco with no return of manure. 

 The average yield of tobacco for complete fertilizer for 

 five years is 1,497 lbs., while for nitrogen and phospho- 

 rus it is 1,431 lbs., a gain of 66 lbs. per acre for the use 

 of potash. There is not enough known about the effects 

 of the various fertilizer elements on hurley tobacco to 

 say whether they affect the quality sufficiently to justify 

 their use on the highly phosphatic Central Kentucky 

 soils. Certainly the yield can be made without commer- 

 cial fertilizers. Such fertilizer experiments as have been 

 recently conducted on the Experiment Station farm with 

 tobacco do not show any material increases. Of course, 

 this statement implies the maintenance of nitrogen with 

 organic matter. 



These results seem to be contradictory to the results 

 obtained in the fertilizer experiments conducted on the 



