TOBACCO INVESTIGATIONS. 



21 



amounts of organic matter increases the weight of the crop to a marked 

 extent. In these experiments the organic matter was apphed in the form 

 of peat in varying amounts, from 2 to 4 tons, on a 12 per cent moisture 

 basis. Tlie following tabulation will show the increase in yield resulting 

 from the addition of organic matter, all other factors in the fertilization 

 being the same. 



Table IV. — Increase in Yield resulting from Application of Peat to Certain 



Soils.' 



Plot No. 



Peat Ap- 

 plication 

 (Tons per 

 Acre). 



Averaee 



Yield 



of Peat 



Plots 



(Pounds 



per Acre). 



Average 

 Yield of 

 No-peat 



Plots 

 (Pounds 

 per Acre). 



Per Cent. 

 Increase. 



A, F, K, 



B, G, X. 

 26, 23, 

 1.4. 6, 

 R, O, 



1,470 

 1,400 



1,570 



1,330 



1,420 



1 The plots received uniform fertilization aside from peat. Manure plots, and peat and acid 

 phosphate plots, gave still higher yields. 



While these data have been obtained for only two years as j^et, it is 

 believed that they are sufficiently striking to warrant tentative conclu- 

 sions being made, particularly as the check plots which contained no 

 additional organic matter were subjected to the same conditions as regards 

 planting, cultivating, etc. 



Except in certain rare cases the application of organic matter in the form 

 of peat would be out of the question on account of the excessive cost of 

 the material and the labor involved in- carting and spreading. How 

 can we add organic matter to our soils at a cost sufficiently low to he practicable? 



There are several ways in which this may be done. There is added to 

 soil a considerable amount of organic matter from stalks, cottonseed meal, 

 manure, etc., but naturally this is not sufficient to replace the losses. 

 Heavy manuring will apparently be sufficient sometimes, but this is an 

 expensive form in which to apply organic matter. We cannot afford to 

 practice any extended system of rotation, but we can supply an enormous 

 amount of organic matter by "cover-cropping" or planting a crop in the 

 fall after the tobacco is taken off, and plowing it under in the spring 

 before planting. 



Cover Crops. 



Cover-cropping should be practiced wherever possible, not only as a 

 means of adding organic matter to the soil but also to prevent washing 

 and blowing, in the case of light .soils. 



