480 MISCELLANEOUS FARM SUBJECTS 



at cotton-oil mills justifies the exchange of seed for cotton-seed meal, 

 to be used as the source of nitrogen in a concentrated manure. If, 

 however, only small quantities of such manures are to be had, and 

 it is desired to use them as direct fertilizers, it is more profitable to 

 compost them with acid phosphate (preferably containing a small 

 percentage of potash) than to use them alone. It is more profitable 

 to compost directly in the drill at time of planting than in heaps 

 previously. 



(6) Cotton may wisely be assigned a place in a judicious rota- 

 tion system. Upon lands devoted to staple crops a three years' rota- 

 tion small grain, corn (with peas,) cotton is judicious. Each 

 crop in the rotation should be appropriately fertilized. It is in evi- 

 dence that the cumulative effects of such manuring upon the suc- 

 ceeding crop are marked. 



(7) Upon the great majority of the soils of the cotton-growing 

 States it is advisable and profitable to use, as a concentrated fertilizer, 

 a complete manure, i. e., one containing soluble phosphoric acid, 

 available potash, and available nitrogen, rather than a manure con- 

 taining only one or two of these ingredients. Nitrogen, however, 

 may probably be advantageously omitted from the concentrated fer- 

 tilizer, in whole or in part, when the soil has previously been liberally 

 supplied with this ingredient, through barnyard manure, green man- 

 uring, etc. 



(8) Soluble phosphates are very much to be preferred in the 

 fertilizer for cotton to those which are not soluble. 



(9) There is no great difference, if any, in the agricultural 

 value and profit, when used in the fertilizer for cotton, of the various 

 soluble potash salts to be had in commerce, except proportionately 

 to the price and content of actual potash. 



(10) Of the nitrogen compounds available for use in fertilizers 

 the organic forms (vegetable and animal) are perhaps best suited 

 to cotton, if one form alone be used, although nitrate of soda is 

 probably nearly if not quite of equal value. Further experiments 

 are needed to determine the efficacy of mixing various nitrogen 

 compounds in different proportions. 



(11) The most judicious proportions of soluble phosphoric 

 acid, potash, and nitrogen in a complete fertilizer for cotton can not 

 be said to have been as yet determined with entire accuracy. Those 

 suggested by Georgia nitrogen 1, potash 1, phosphoric acid 3 l /2 

 and by South Carolina nitrogen 1, potash %, phosphoric acid 

 2*4 perhaps approximate reasonable accuracy. In the light of 

 present information, perhaps nitrogen 1, potash 1, phosphoric acid 

 2% or 3 would not be injudicious proportions for general use. 



(12) The amount of concentrated fertilizer which may profit- 

 ably be used per acre varies widely with the nature and condition 

 of the soil, the seasons, and other circumstances. For an average 

 soil in fairly good condition perhaps the maximum amounts indi- 

 cated by Georgia (nitrogen, 20 pounds; potash, 20 pounds; phos- 

 phoric acid, 70 pounds), or by South Carolina (nitrogen, 20 

 pounds; potash, 15 pounds; phosphoric acid, 50 pounds), or an 



