EXPERIMENT STATION BULLETINS. 457 



ing points should be remembered: That water-soluble nitrogen is 

 readily available for plant uses, and that the water-insoluble nitrogen 

 ("active insoluble" and "inactive insoluble") may or may not be readily 

 available for plant uses. 



When the amount of '^active insoluble^' nitrogen is greater than the 

 amount of "inactive insoluble'' nitrogen, the total water-insoluble nitro- 

 gen is considered to be readily available to plants; ivhen the amount of 

 ^"'active insoluble'' nitrogen is less than the "inactive insoluble" nitrogen 

 the total water-insoluble nitrogen is not considered to be readily avail- 

 able and the plants may fail to derive any benefit from its use. 



Many of the fertilizer brands reported in this bulletin, especially those 

 having small percentages of nitrogen, show a large proportion of the 

 nitrogen to be in water-insoluble forms of questionable quality. 



CONCERNING PRICES. 



Owing to the continued demand from other sources, for many of the 

 materials used in the fertilizer industry, there is no hope for a reduction 

 in the prices for the coming season. 



Nitrate of soda has advanced about |20.00 per ton and this has caused 

 a stiffening in the price of practically all ammoniates. Acid phosphate 

 will be from three to five dollars per ton higher than the average price 

 two years ago and potash will undoubtedly cost the purchaser not less 

 than 15.00 per unit in mixed fertilizers. 



No domestic sources of potash of any consequence have been found in 

 this country to replace that which formerly was imported from Germany. 



Under these conditions it behooves every person who contemplates 

 the use of commercial fertilizers next spring, to consider well the needs 

 of his soil and to purchase that brand or formula that will supply the 

 needed elements at the least cost, keeping in mind the availability of the 

 nitrogen, whenever this element is purchased. 



NU-LIPB FERTILIZER. 



Attention is called to this fertilizer which was offered for sale in the 

 State during the past season by the Mineral Fertilizer Company, Chi- 

 cago, Illinois. It was guaranteed to contain 15 per cent phosphoric 

 acid. No claim was made for available phosphoric acid although in a 

 letter addressed to the senior author under date of December 11, 1915, 

 the material was stated to be basic slag. In the advertising circulars 

 sent out, the following statements were found : 



"The basis of Nu-Life Fertilizer is Slag Meal." 



'^Nu-Life Fertilizer is slag meal and additional available phosphoric 

 acid." 



An investigation as to the nature of this material proved it to be a 

 mixture consisting of about equal parts of raw rock phosphate and slag 

 from an open hearth iron furnace. As this open hearth slag contains 

 less than 4 per cent of phosphoric acid, it is at once evident that, at 

 least, 85 per cent of the phosphoric acid in Nu-Life Fertilizer is derived 

 from raw rock phosphate and its commercial or agricultural value should 

 be no greater than that of rock phosphate of the same grade. Kock phos- 



