ANALYSES OF NOVA SCOTIAN SOILS. HARLOW. 343 



What is the availability of the plant food in Nova Scotia 

 soils? Four samples collected by the writer and analyzed at 

 Ottawa under the direction of Professor Shutt gave as follows: 





Lime 



Potash 



Phosphoric acid 





Acd 

 soluble 



Avail- 

 able 



Acid 

 soluble 



Avail- 

 able 



.048 



Acid 

 soluble 



Avail- 

 able 



1 — Good soil 



1.64 



.99 



.27 



.23 



.087 



2 — Virgin soil .... 



.04 







.145 



.105 



.026 



.011 



3— 



.36 



.15 



.37 



.019 



.11 



.023 



4— 



.11 



.02 



.42 



.018 



064 



.023 



Of the important plant foods nitrogen, lime, phosphoric 

 acid, and potash, consider first potash. We regard it as 

 existing in the soil in the easily soluble or availab-le form; the 

 more difficult soluble or acid soluble and the insoluble part; 

 for example a soil analyzed: 



POTASH 



Insoluble in acid 737% ^ 



Acid soluble 149% [ "^^^ % unavailable 



Available ■ 02 % 



That is, there are 45 times as much insoluble potash as 

 available. 



Dyer, in Proc. Royal Society, 1901, says that less than 

 .01 to .03 per cent of available phosphoric acid in a soil 

 indicates the need of phosphate manures and that soils with 

 .01 per cent of available potash probably require no applica- 

 tion of potash manures. 



Hence, from Dyer's statement and the analyses in 

 Tables 1-5 we can say that our soils have a good supply of 

 potash but available to a limited extent. Comparing soil 

 No. 1, which has a good supply of lime and organic matter, 

 with Nos. 2, 3, and 4, low in these components, one may 

 account for the greater proportion of available potash in No. 1. 



