ANALYSES OF NOVA SCOTIAN SOILS. HARLOW. 345 



England, 1429 pounds per acre to the depth of nine inches 

 were carried away in the drainage water per year, or in the 

 forty years of the experiment, about 28 tons per acre. 

 Limestone has the following uses in the soil: — 



(1) To supply calcium, a necessary element of plant food; 

 4 tons of clover per crop, for .30 crops would require 

 3,510 pounds of Calcium. 



(2) To neutralize the acids resulting from the decay of or- 

 ganic material or the decomposition of such fertilizers as 

 ammonium sulphate. Very often the soils with the 

 least organic matter show the least lime and vice versa; 

 e. g., a muck soil at Truro shows at the surface: — 



Inorganic Volatile Lime 



matter. matter. 



At surface 7% 85.90% 3.20% 



1st ft. of subsoil 79% 15.73% 1.40% 



(3) To effect a chemical dissolving of potash silicates and to 

 set free phosphoric acid from iron and aluminum phosphates. 



(4) For its flocculating effect on the clay soils. 



Caustic Lime, CaO, has an antiseptic effect on the soil. 

 Hutchinson of Rothamsted Exp. station, England, in June, 

 1913, says: "Caustic lime is a valuable antiseptic and when 

 applied to the soil, even in the presence of large quantities of 

 carbonate of lime, disturbs or destroys the state of equi- 

 librium existing between the micro-flora and micro-fauna of 

 the soil; it kills many bacteria and destroys the larger protozoa 

 which exert a depressing effect on bacterial growth; the 

 inhibitory action of caustic lime on soil bacteria persists 

 until all the oxide is changed to the carbonate; this is followed 

 by a period of active bacterial growth. 



Organic Matter and Nitrogen. 



Table 4 gives averages of the organic matter and nitro- 

 gen in the three groups of soil studied: these indicate organic 



