New York Agricultural Experiment Station. 243 



this basis are given in Table V. The figures given are the aver- 

 ages of two boxes. 



Table V. — Phosphoric Acid Availability Experiments: Yield of Air-dry 



Matter, 1896-7. 



The foregoing data are not such as to permit of any comparison 

 of the relative efficiency of the various phosphates with the 

 different crops, because in general the boxes receiving no 

 phosphoric acid were nearly or quite as productive as those that 

 did. It is interesting to note, however, that the fertilizers in- 

 creased the productiveness of the soil for the vetch much less 

 than for the other crops. 



Availability of various phosphates to different crops in a soil 

 composed of quartz sand. — In these experiments determinations 

 were made of the dry matter produced by the various boxes, 

 and also of the quantities of phosphoric acid taken up by the 

 several crops. Tables VI and VII show the yields of dry matter 

 and Tables VIII and IX the quantities of phosphoric acid 

 utilized. 



Table VI. — Phosphoric Acid Availability Experiments: Yields of Dry Mat- 

 ter on Different Phosphates, 1898-9. 



Acid phosphate 



Florida rock (floats) . 



Thomas slag 



Redonda phosphate 



(dehydrated) 



No phosphoric acid. . 

 No fertilizer 



Barley. 



Grams. 



189.6 



9.3 



181.4 



150.1 



7.9 



10.9 



Mil- 

 let. 



Grams. 

 29.2 

 1.1 

 8.8 



14.4 

 1.2 

 1.1 



Oats. 



Grams. 

 210.2 

 9.1 

 198.9 



170.2 

 6.8 

 10 



Clover. 



Grams. 

 93.8 

 2.6 

 74 



37.1 

 2.4 

 4.5 



Vetch. 



Grams, 

 88.5 

 31.8 

 67.5 



61.9 



2.7 

 2.7 



Toma- 

 toes. 



Grams. 



58.7 



1.8 



48.4 



57.2 



Cab- 

 bage. 



Grams. 

 82.2 

 64.5 

 80 



65.4 



.5 



3.6 



Rape. 



Grams. 

 91.4 

 72.3 

 98.4 



74.9 



.8 



3.4 



