180 ALFALFA FARMING IN AMERICA. 



cause I have seen such, good effects come from its 

 use in England, and because it did equally well on 

 Woodland Farm. It will never perhaps be cheap 

 enough for use west of the Allegheny Mountains, 

 since it is all imported from England or Germany, 

 but along the Atlantic seaboard it is now probably 

 as cheap a source of phosphoric acid as anything 

 known. With basic slag one gets quite a little lime 

 free of cost, since usually there is about 55% of 

 carbonate of lime in basio slag. It should sell for 

 about $1 per unit; that is, a slag analyzing 18% 

 phosphoric acid should sell for $18 per ton, when it is 

 about as cheap as any other source of phosphorus 

 with the lime thrown in. 



In England on old pastures basic slag works 

 miracles. There with the sowing of no seeds at all 

 clovers spring up and cover over the land, almost 

 crowding out the grasses. The lime has sweetened 

 the soil, the phosphorus fed it, the clovers result. 

 Later the decay of clover leaves and stems fill the 

 soil with available nitrogen which in turn feeds the 

 grass. When will we learn in America to feed soils 1 



Other Sources of Phosphorus. — ^Prof. Alfred 

 Vivian, of the Ohio State University, sO' clearly and 

 concisely states the composition of phosphatic fer- 

 tilizers in his admirable little book, "First Prin- 

 ciples of Soil Fertility," that we here quote ; 



Phosphoric acid is present in the soil in much smaller quan- 

 tities than potash, and experience shows that it is much more 

 likely to become exhausted. In fact, there are sections of the 

 country where no other fertilizers than those furnishing phos- 

 phoric acid are used, while these are bought in large quantities. 



