SOILS AND FERTILIZERS 481 



approximate mean of the two would be the maximum limit of profit- 

 able application. The actual weight of the complete fertilizer 

 furnishing these quantities would, of course, vary with the percent- 

 age composition in nitrogen, potash, and phosphoric acid of the 

 materials used to make the fertilizer. If the commercial "am- 

 moniated" fertilizer or other concentrated manure intended for use 

 under cotton should be compounded (as it might very well be, and 

 in some cases is) to analyze approximately 



Per cent. 



Soluble (available) phosphoric acid 9 



Potash 3 



Nitrogen 3 



then 700 pounds per acre of such a fertilizer would be approximately 

 the maximum amount that could judiciously and profitably be used, 

 under ordinary circumstances, upon soil in good condition. 



(.13) The concentrated fertilizer should be applied in the drill 

 (not broadcast) at a depth of not more than 3 inches, and well 

 mixed with the soil. 



(14) All things considered, it is perhaps best in most cases 

 to apply all the concentrated fertilizer in one application at the 

 time of planting. With lands in superior condition, however, or 

 where large quantities of fertilizers are used, it is probably profitable 

 to apply half at planting and half at the second plowing. 



Yield From the Use of Fertilizers on Cotton as Compared WitH 

 Yield from Unfertilized Soil. The results of experiments instituted 

 vary greatly with the nature of the soil, the seasons, the culture, 

 and the kinds and amounts of manures employed. With the ex- 

 ception of those upon one class of soils, however, they all agree in 

 demonstrating that large profit attends the judicious manuring of 

 cotton. The exception is in the case of the black prairie or cane- 

 brake soils of the alluvial formations of the Gulf States. Experi- 

 ments upon such soils at the Alabama stations indicate that no 

 compensating returns may be expected from the use of manures 

 except crushed cotton seed and cotton-seed meal, and even with 

 these the returns are small. Drainage and good mechanical tillage 

 seem to be the chief need of these soils. Upon other soils of Ala- 

 bama, however, the percentage of profit from a judicious use of fer- 

 tilizers, followed by intelligent cultivation, is most satisfactory. 

 Upon a poor sandy soil, with no retentive clay within 3 feet of the 

 surface, even with unusual expense for fertilizers, the increase re- 

 sulting from the use of economical manures paid 85 per cent profit 

 on cost. 



Experiments made under direction of the Arkansas Station in- 

 dicate that fertilizers are generally remunerative, the percentage of 

 profit ranging from 20 to 180. Five hundred pounds per acre of 

 rotted cotton seed gave a net profit of $3.93. Five hundred pounds 

 each of cotton seed (at $6.50 per ton) and cotton-seed meal (at 

 $20 per ton) gave equal financial profit. 



At the Georgia Station the use of commercial fertilizers was 

 almost always profitable, the percentage of profit ranging from 5 



