I'lO DEPARTMENT OF AGRICULTURE GEORGIA. [406] 



zer absolutely uniform throughout its plat, and the same 

 number of plants should grow upon each. 



An accurate record should be kept of the date and man- 

 ner of preparation, the application of fertilizers, planting, 

 each cultivation and the seasons ; and the crop, when ma- 

 ture, should be gathered and accurately weighed from each 

 plat separately. If there is an abundance of potash already 

 in the soil, and in an available form, there will be no in- 

 crease in the crop from its application ; if deficient, the in- 

 creased production from its use will indicate that it was 

 needed. If the increase is still greater from the use of 

 potash and phosphoric acid combined, this result will indi- 

 cate that both of these substances were deficient in the soil. 

 If a still greater increase results from the use of nitrogen, 

 phosphoric acid and potash combined, this result will indi- 

 cate that t*f.e soil was deficient in all three of these sub 

 stances. If there is no increase of the crop, as the result of 

 the use of any one of the substances, the indications are 

 that the soil contained a sufficient amount of that substance 

 for the production of the crop upon which the experiment 

 was made. 



This experiment, if carefully conducted for several years 

 on any particular soil, will very clearly indicate what fer- 

 tilizing substances are needed in that soil. It must, how- 

 ever, to be reliable, be conducted on each variety of soil, 

 and by each farmer for his own information, since one soil 

 may be deficient in one substance, and perhaps the adjoin- 

 ing field, or even another part of the same field, be deficient 

 in another. Every farmer should conduct such experiments 

 on every variety of soil on his farm. They cost but little, 

 and may save him the expense of purchasing, in the so- 

 called complete fertilizers, costly substances with which his 

 land is already well supplied. 



I 



