394 



APPENDIX 



LOSSES IN CROP REMOVALS 



In the following table the amounts and commercial values of the three 

 limiting elements removed per acre by several important vegetable and farm 

 crops are presented. (From Illinois Station.) 



Fertility Removed per Acre by Important Vegetables and Farm Crops ' 



1 Compiled chiefly after Wolf and Goessman. 



2 In computing the values 1915 prices are used; 20 cents per pound has been allowed for 

 the nitrogen, 10 cents for the phosphorus, and 6 cents for the potassium. These are the 

 approximate prices prevailing at present for three elements in nitrate of soda, steamed bone 

 meal, and potassium sulfate. 



SOURCES OF PLANT FOOD 



The following tables are taken from Illinois Station Circular 182. 



Table 1. — Dry Matter and Nitrogen in Growth per Acre: (Delaware Experiments) 

 {Expressed in pounds) 



Legume 



Soybeans.. . 

 Cowpeas. . . . 

 Hairy vetch 



Table S. — Dry Matter and Nitrogen in Growth per Acre: {Cornell Experiments) 

 {Expressed in pounds) 



