EXPERIMENT STATION BULLETINS. 



447 



Acid plMtspluiie is sometimes ai)plie(l in the hill for corn or ])otatoes 

 that is where small apjilications are made. Tliis is not generally advisable 

 iiiasmnch as the crops that follow <lo not receive ninch benefit from 

 tlie residues. Some broadcast it by hand after the land is plowed and 

 work it into the soil when the seed bed is being prepared. The majority 

 of farmers, however, apply it by means of the fertilizer drill or attach- 

 ment on tlie grain drill. In some cases it is sprinkled over manure in the 

 spreader and applied along with it. 



Tlie fact should not be ovei-looked that the efficiency of these fertilizers 

 is dependent upon their thorough incorporation with the surface layer 

 of soil. i 



Tlie reinforcement of farm manure with phosphorus is sound practice. 

 Parm manure in comparison witli commercial fertilizers is unbalanced. 

 Itniay be cited for example that a 2-8-2 fertilizer mixture or one con- 

 taining two per cent of ammonia, eight per cent phosphoric acid and two 

 ])er cent potash is widely nsed. Ordinarily mixed farm yard manure 

 contains about .5 per cent nitrogen, .25 per cent phosphoric acid and .0 

 per cent potash, thus being deficient in phosphoric acid. By supple- 

 menting the manure with phosphorus smaller applications of manure 

 may be made with better results. 



Pliosp/ior/c Acid 



Re)d.t/Ve 



Amounts of nitro^zi^, phospborio ac('c/, and potd&fi 

 In d 1-%-Z commercial j-e.rtilizzr. 

 Figure H. 



