254 CROP GROWING AND CROP FEEDING 



acre has been with 1,100 pounds per acre of fertilizer containing phosphoric 

 acid, nitrogen and potash. Muriate of potash and nitrate of soda, when 

 used alone, have not given a profitable increase, but have proved beneficial in 

 connection with superphosphate. Phosphoric acid seems to have been the 

 controlling element in an increase in the potato crop in all of our experi- 

 ments." 



This shows the importance of testing the needs of the soil experimental- 

 ly, for, as we have seen in the Pennsylvania experiments, phosphoric acid had 

 less effect than potash alone, and the same was found to be the case in 

 Kentucky. But in one co-operative experiment given in the Kentucky bulle- 

 tin it was shown that on a soil different from that of the Station the same re- 

 sults were had as detailed by the Ohio Station, showing a great variation in 

 the manurial requirements of different soils, even in the same State. 



At the Texas Station it was found that potash, either as a muriate or sul- 

 phate, produced a paying crop, and that bone black was the best one-sided fer- 

 tilizer. In regard to the Southern second crop seed potatoes the Texas Sta- 

 tion says: "So far as our experience goes, it seems safe to conclude that sec- 

 ond crop potatoes are as good, if not better, for planting, than Northern 

 grown seed." 



