194 PRINCIPLES OF AGRICULTURAL CHEMISTRY 



in bushels per acre, based on the quantity of nitrogen removed 



JO+ Of .OB .10 .11 



.16 ./a .& 21 



Fig. 44. Relation of total nitrogen to the average weight of the crops 

 grown without addition of nitrogen in pot experiments. 



500 



\ I 



os wif/touf- Ntfrogefi 



PERCENTA GE5 OF NITROGEN IN SOIL 



Fig. 45. Relation of total nitrogen of the soil to the average effect 

 of fertilizer nitrogen in pot experiments. 



from the soils in pot experiments, is given in the following table 



