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Bacteria in Relation to Country Life 



soil; the rock particles give up some of their constituents 

 which serve as nourishment for the soil bacteria, as 

 well as for the higher plants. The microorganisms, 

 under such conditions, grow in numbers and vigor. 



Fig. 19. Colonies of soil bacteria. 



It is for this reason that in the warm summer months 

 the mpist soil is in slighter need of additional fertiliza- 

 tion. The chemical and bacterial activities are then 

 intense enough to provide for an adequate supply of 



