4 FERTILIZING TOBACCO 



grown without the stalk, roots ,etc, The analyses of the 

 whole plant made by Prof. Stockbridge indicate the follow- 

 ing plant food requirements. He found the average 

 Florida tobacco plant to contain: 



PHOSPHORIC ACID NITROGEN POTASH 



0.99 per cent. 2.58 per cent 4.34 per cent. 



This indicates that the crop requires its plant food in 

 the proportion of 260 Ibs. of Nitrogen and 440 Ibs. of Potash 

 for every 100 Ibs. of Phosphoric Acid actually taken up by 

 the plant. As Phosphoric Acid is apt to change into 

 insoluble forms in the soil, allowance must be made for 

 such losses in making up special fertilizers. Again, many 

 soils accumulate supplies of Nitrogen through the growth 

 of legumes in rotation, and a too free supply of Nitrogen in 

 the fertilizer, may prove very undesirable by inducing a 

 too rank growth of leaf. For these reasons, many experi- 

 enced tobacco growers use a higher proportion of Phos- 

 phoric Acid, and a lower proportion of Nitrogen than the 

 chemical composition of the crop would seem to require. 



Prof. Stockbridge's recommendation for fertilizer appli- 

 cation is based on these conditions, and his formula sup- 

 plies the necessary plant foods, (as shown by the analyses) 

 which will be removed from an acre of land by a fair crop 

 of tobacco. 



The conclusions of accepted authorities may be thus 

 stated; The demands of the crop for Phosphoric Acid are 



