13 

 Cost of High-analysis vs. Low-analysis Fertilizers. 



The above table emphasizes the lower plant food cost of the various constituents 

 when purchased in high-analysis (14 per cent or over of available plant food) 

 mixtures. Comparisons also show a higher activity of the water insoluble nitrogen 

 when purchased in this form. 



It is very gratifying to note that the campaign for the purchase of high-analysis 

 fertilizers that has been waged in our control bulletins for so many years, has 

 resulted in the selection of an increasingly large tonnage of high-analysis goods. 

 Most of our farmers realize that the purchase of low-analysis fertilizers is poor 

 economy. 



Chlorine in Tobacco Fertilizers. 



It is usually the custom to select materials which are comparatively free from 

 chlorine when making up a mixture for the tobacco crop, particularly when the leaf 

 is to be used for cigar wrappers or binders, as experiments have shown that chlorides 

 contribute to a dark ash. The limit of tolerance for chlorine in this respect has 

 never been worked out, and it may be possible that other factors contribute to this 

 condition, but inasmuch as the trade demands a mixture with little chlorine present, 

 it may not be out of place to note the statistics for the year with reference to the 

 subject. 



Fifty-three brands of tobacco fertilizer were examined. The chlorine content 

 varied from .22 per cent to 1.94 per cent, with an average of .66 per cent, equivalent 

 to .88 per cent of potash (K2O), or 1.39 per cent of muriate or chloride of potash. 

 It is probable that somewhat over one-half of this chlorine comes from the potash 

 salt used in the mixtures, although it is not an uncommon occurrence to find .3 

 per cent of chlorine in mixtures which have had no addition of potash salt. The 

 average amount of chlorine found in tobacco fertilizers probably does not contribute 

 seriously to an undesirable ash. 



Vegetation Pot Experiment to Determine the Nitrogen Availability of 

 Pulverized Poultry Manure and Rehmsdorf Tankage. 



Both of these ammoniates are commercial products for which the manufacturers 

 claim a high nitrogen availability. The Pulverized Poultry Manure is sold by the 

 Premier Poultry Manure Co., of Chicago. The Rehmsdorf Tankage is a leather 

 tankage imported from Germany by Bergstrom, Stoeve & Co., Inc., 223 Broadway, 

 New York. 



The availability of the nitrogen in these materials was determined by the vegeta- 

 tion method. The experiment was conducted according to the general methods 

 described on page 11 of Control Bulletin No. 25, varied only in detail to suit the 

 needs of this particular investigation. The soil used was the same as was there 

 described. Millet was the crop grown. Results were determined both in yields 

 of dry matter and in the total amount of nitrogen contained in the above-ground 

 parts of the plant. In the following table, results are presented: 



