PHOSPHORUS FOR PASTURES 297 



Mineral Manures on Pastures. Lime is the bedrock of 

 good grass pasture. After lime, comes the need of phos- 

 phorus and potassium. Most soils in the United States 

 have in them now a good supply of potassium. The ex- 

 ceptional soils are those derived from peat and sandy 

 lands. Peaty soils may be so deficient in potassium, 

 though not all of them are, that the grasses growing on 

 them will have little value. Sandy soils are more often 

 in need of potassium, but on such soils pastures are, as 

 yet, rarely established. Phosphorus is the substance 

 more commonly needed in soils; in fact, there are few 

 soils in the world that are as rich in this element as would 

 be best for plants. The one region that I call to mind 

 now that is not benefited by use of more phosphorus 

 than is native to the soil is the bluegrass region of Ken- 

 tucky. There are parts of this region that show about 

 5 per cent of phosphoric acid in its subsoil, and many 

 small nodules of phosphatic rock are scattered through 

 the earth within easy reach of plant roots. I have tested 

 several forms of phosphorus on permanent pasture in 

 Ohio, but unfortunately have no figures showing re- 

 sults. Apparently the best results were secured by a 

 very liberal use of floats or finely-ground phosphatic 

 rock distributed right over the thick sod of an old pas- 

 ture. Of this substance nearly a ton to the acre was 

 used (it costs about $8 per ton in large lots) and it is 

 plain to see that the result has been a doubling of the 

 grass and a great increase in the number of clovers in 

 it, beside a distinct difference in color of the herbage. 

 I applied also a sprinkling of stable manure, which com- 

 plicates the situation, but I have no doubt that I will 



