THE CULTUliE OF TOJlArCO. 135 



soluble and more available for the plant, but, at the same time, the 

 percentage of actual phosphoric acid to the ton of fertilizer is 

 I'educed. The sulphuric acid in the superpihosphate may prfjve 

 injurious to the combustibility of the leaf, and surely will if there be 

 any great excess of it present. The better form, after all, may be to 

 apply the rock or bone in as finely ground form as possible, and let it 

 become available through the action of the soil, the weather, and the 

 plant juices. 



Lime is an essential to the gnjwth of the plant, but nifist soils 

 contain sufficient for the actual needs of the tobacco plant. Lime's 

 chief value to the crop lies in a secnndary action. Where the siiil is 

 acid it corrects the acidity, and piomotes nitrification by encouraging 

 the action of the nitrifying bacteria. In the heavy clcse clay soils 

 it promotes floculation, or the combination of the small paiticles 

 of the clay into larger bodies, thus making the soil moie frialsle, easy 

 of cultivation, more lapidly di-ained, aerated, and better adapted to 

 the production of roots and the development of plant life. It has 

 also the power of making certain food mateiials in the soil, that have 

 become insoluble and non-available, of use to the plant by displacing 

 them from their present combinations. This is particularly true of 

 lime's action on potash, and not unfrequently lime is given the credit 

 of being of great value to the plant in the matter of plant food when 

 its action has really been simply to make other materials available. 



A crop of a thousand pounds of leaf, if the stalks be returned tn 

 the field, may be said to remove from the snil about forty pounds of 

 nitrogen, five pounds of phosphoric acid and fifty pounds of potash. 

 This does not mean, however, that only this amount of these elements 

 must be available, or be added to the soil each year, to produce a good 

 tobacco crop. The tobacco plant makes its growth in about sixty days, 

 and fertilizers to be available t'l the growing crop must be in an ea.sily 

 soluble form. Where the fertilizers are added in forms that aie not 

 easily soluble larger amounts must be used. The tobacco roots do not 

 reach and secure all the materials present in the soil and available ; 

 therefore allowance must be made in the fertilization for this, and 

 also for the fact that some of the more soluble forms "null be washed 

 out by the rains and lost. The soil already contains amounts of the 

 elements needed, and, if it be well Ijalanced, it may not be necessary to 

 fertilize heavily for several yeai-s. However, if the process of deple- 

 tion without restoration be continued, the soil will become exhausted 

 and of little value. It is a much easier process to maintain the 

 fertility of the soil than it is to restore it. 



Several methods of applying the fertilizers to the soil are in use. 

 It may be broadcasted or drilled into the field so as to be evenly 

 distributed, or it may be placed in furrows made along the rows where 

 the plants are to be set, or again, it may be placed around the plant. 

 No one method can be recommended for all occasions. Barnyard 

 manure is applied evenly over the field and ploughed in. This should 

 be done some time before the planting season, if possible, so as to allow 

 the decay to get well started, and to permit the heat of the first 

 fermentation to subside. Where commercial fertilizers have to be 

 purchased, the best results for the money may be obtained by placing 

 them where the plant can utilize them as far as possible during the 

 growing season. This may be done by distributing them in the 

 fuiTow when the ridge is being thi-own up in the ridge system of 

 planting, or by distributing them along the marked row with a 



