CONTENTS. 



composition, and results of 



Summary, ...... 



Introduction, ..... 



Relation of Massachusetts agriculture to soil 

 chemical analysis, . 

 Composition of Massachusetts soils, . 

 Relative need of phosphoric acid and potash, 

 Experimental results. 

 The potato, 

 The corn crop, . 

 The hay crop, . 

 Asparagus, 



Soy beans, oats and rye, 

 Cruciferce, 

 Experiments for comparison of different phosphates, . 



Comparison of phosphates on the basis of equal money's worth, 

 Phosphates compared on the basis of equal annual application of 

 phoric acid, ........ 



Plant-food elements applied, ..... 



General treatment, ....... 



Crops grown, ........ 



Relative profits on the different phosphates, 

 Cumulative effect, ....... 



Indirect or secondary effects, ....... 



Effect on soil acidity, ....... 



Sulfur supplied, ........ 



Beneficial secondary effects from the use of soluble phosphates, 

 Rapid early growth of both roots and tops, . 

 Increase in tillering of cereal grains, .... 



Earlier and more perfect ripening, .... 



Effect on the availability of soil constituents, 



Larger gain of atmospheric nitrogen, .... 



Conclusions, .......... 



Relative phosphate needs of different crops. 



pho; 



P.^GE 



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Approved by 

 The State Board of Publication. 



