﻿THE CULTURE OF FLUE-CURED TOBACCO. 11 



Potash, like ammonia, improves the body of the leaf, and it has 

 a decided value in tending to diminish or prevent " diseasing " or 

 "specking." On the light, sandy soils of the New Belt section 

 especially, potash should be applied much more liberally than is now 

 the general custom. 



Phosphoric acid may be considered the most generally needed 

 plant-food material throughout the tobacco-growing region under 

 consideration. It not only increases growth but hastens maturity, 

 and also strongly tends to brighten the color because of its decided 

 effect in ripening the leaf. By reason of this specific effect in thus 

 improving the quality phosphoric acid should be used liberally in 

 the tobacco fertilizer, particularly on the better improved soils, 

 which, from an accumulation of nitrogenous materials, might tend 

 to produce -a dark, coarse leaf. On the other hand, some caution 

 should be exercised not to use it excessively on unimproved very 

 light soils. " On such soils there is natural danger from premature 

 ripening, or " firing," as it is usually called, and such tendency would 

 be increased by an excessive application of phosphoric acid, though 

 increasing the ammonia supplied in the fertilizer or otherwise would 

 tend to overcome this difficulty with probable increased growth as 

 well. This largely explains why the turning under of a leguminous 

 crop immediately preceding tobacco on such unimproved very sandy 

 soils may sometimes result in positive benefit. 



Generally speaking, phosphates (except as just indicated) and 

 potash may be used freely on flue-cured tobacco without injury to 

 the quality, but it requires nice adjustment of the ammonia supply 

 to give the best results. As stated, too little will make a " poor," 

 thin tobacco of small growth, while too much will tend to make the 

 tobacco dark, coarse, and rank smelling. Ammonia in the soil comes 

 almost entirely from decaying vegetable matter or manure, and the 

 quantity of ammonia to be used in the fertilizer will depend largely 

 on how much may be expected from these sources in the soil. A crop 

 of 1,000 pounds of tobacco to the acre, to produce the leaf, stalk, and 

 roots, will need to assimilate about 75 pounds of ammonia (equiva- 

 lent to approximately 62 pounds of nitrogen). On poorly improved 

 sandy soils, generally producing around 600 pounds of tobacco to 

 the acre under ordinary fertilization (say, 500 pounds of 3-8-3 fer- 

 tilizer to the acre) , the yield and quality generally could be improved 

 greatly and the crop made more profitable by using an increased 

 amount of ammonia in the fertilizer. On such a soil, out of the 

 75 pounds of ammonia necessary to produce a 1,000-pound crop it 

 would not be unreasonable to supply in the fertilizer 40 or 50 pounds 

 of this material (equivalent to 250 or 300 pounds of 16 per cent 

 dried blood). 



