138 STATE BOARD OF AGRICULTURE. 



may desire. But after the guarantees are made, the manufacturer 

 should be made to adhere to it so closely that the essential character 

 of a brand is maintained, and its value shall not fall far below the 

 value of the guarantee. 



PRICES USED IN VALUATION OP FERTILIZERS. 



In determining comparative values of fertilizers, the following prices 

 have been used : Nitrogen, llYo cents per pound ; potash, soluble in 

 water, 6 cents per pound; available phosphoric acid, 6 cents per pound; 

 in bone, total phosphoric acid, 3% cents per pound; in mixed fertilizers 

 containing nitrogen, insoluble phosphoric acid, 2 cents per pound; in 

 fertilizers containing no nitrogen, no value is given to insoluble phos- 

 phoric acid. 



It must be distinctly understood that these prices are not intended 

 to represent the agricultural value of the fertilizer; that is, the return 

 which may be expected from its use. Neither do they represent the 

 retail cost to the farmer, of the several elements in mixed fertilizers, 

 but they simply represent approximately the cost of the different ele- 

 ments in the raw and unmixed materials. 



They are used solely for the purpose of comparing the value of the 

 fertilizers as guaranteed by the manufacturers with the value of the 

 samples analyzed. These prices are often useful to the farmer in com- 

 paring the relative values of two or more similar brands offered by dif- 

 ferent manufacturers. 



BRAND NAMES. 



In making their purchases, buyers should not be guided too much by 

 brand names, for they may or may not bear any relation to the useful- 

 ness of the goods. The words "guano," "dissolved bone," "high grade," 

 etc., very often have no significance and, in fact, may be misnomers; 

 and it often happens that the so-called special fertilizers but poorly 

 suit the nature of the crops whose names they bear. There are no 

 mysterious properties imparted to a fertilizer through its name whereby 

 the plant-food it contains is better suited for the requirements of one 

 certain crop than another; the plant-food contained in a fertilizer 

 branded "Potato or "Sugar Beet Special" will supply the requirements 

 of a corn or wheat crop just as well as those of the crop for which it 

 is named. 



Brand names are entirely unnecessary, and it would be much to the 

 advantage of the farmer if he would always buy his fertilizers on the 

 basis of the plant-food they are guaranteed to contain. 



PURCHASE AND USE OF COMMERCIAL FERTILIZERS. 



Commercial fertilizers should not be used as a substitute for farm 

 manures, but rather to supplement them. 



The amount and kinds of artificial plant-food to be used should be de- 

 termined solely by three factors, namely (a) condition of the soil, (b) 

 requirement of the crop to be grown, and (c) amount of natural farm 

 manures available. 



If a soil is deficient in nitrogen and phosphoric acid and contains a 



