56 



Increase of seed cotton per acre when kainit was added: 



To unfertilized plot 169 lbs. 



To cottonseed meal plot 226 " 



To acid phosphate plot 471 " 



To cottonseed meal and acid phos. plot. ... 98 " 



Average increase with kaiuit 241 " 



The chief need of this isoil was for phosphoric acid. 

 Potash ranked second in efficiency. To a less extent the 

 .vield was increased by nitrogen. The most profitable fertil- 

 izers were the mixtures of cottonseed meal, acid phosphate 

 and kainit; apparently 100 pounds per acre of kainit wa& 

 more profitable than 200 pounds. 



Mr. Logan conducted a fertilizer test on cotton in 1891 

 and again in 1892. All three tests agree in showing that 

 phosporic acid is more urgently needed than any other fer- 

 tilizrng ingredient. They all agree further in showing that 

 the soil of that vicinity responds moderately to nitrogen. 

 They disagree in regard to the effects of potash, muriate of 

 potash in the two earlier experiments proving useless, and 

 kainit in the present experiment proving decidedly benefi- 

 cial and profitable. 



This difference is not strange in view of the fact that the 

 seasons were not alike; that different potash salts were em- 

 ployed, and that almost certainly different fields were used. 

 Apparently the land which in 1897 showed a need of potaish 

 was in poorer condition than the field used in the two ear- 

 lier tests. Apparently a fertilizer for the soils of this lo- 

 cality should consist chiefly of acid phosphate. 

 Experiment Made by A. A. McGregor, 2^ Miles Southwest 

 OF Town ('REEK, Lawrence County. 

 Yellowish red soil, 6 inches deep ; subsoil red. 



Thiis field had been in cultivation at least 70 years. Orig- 

 inal forest growth was red oak, post oak, black jack oak 

 and hickory. The preceding crop was cotton, which wac> 



