32 BOARD OF AGRICULTURE. [Jan. 



that is, nearly three times as much potash as phosphoric 

 acid. But the fertilizer manufacturers tell us that plants 

 want three or four times as much phosphoric acid as potash. 

 Now, who is right ? Do the plants themselves know what 

 they want ? Do they take what they want and in the pro- 

 portion they want it, or are the plants mistaken and the 

 fertilizer manufacturers right? I prefer to believe that the 

 roots of a plant are tolerable judges of what the plant 

 requires for its best development. Plants want potash and 

 phosphoric acid in the ratio of three to one ; they get these 

 materials m prepared fei^tilizers in just the reverse ratio. 



This, you will say, is all theory. Well, yes. It was theory 

 that caused Liebig to give us the greatest of all blessings in 

 agriculture ; namely, soluble phosphoric acid as plant food. 

 It was theory that made possible the great Brooklyn 

 bridge. But let us see if our theory is true when tested by 

 the rules of practice. The following table shows the effect 

 of fertilizers having varying percentages of potash ; the first 

 column shows the percentage of potash in the fertilizer used, 

 and the second shows the value of the increase of crop due 

 to one dollar's worth of fertilizer. 



Prepared fertilizers, 

 Chemicals,* . 



The figures in the last column represent the whole value 

 of increased crop, and, of course, the value of the fertilizer. 

 In all cases one dollar has to be taken from the figures to 

 show the true profit or loss. 



Now you can see that increasing the potash increased the 

 value of the fertilizer, and I am of the opinion that our 



* By chemicals I mean digsolved bone-black, muriate of potash, iulphate of 

 ammonia, krngit, nitrate of soda, etc. 



