FOOD FOR PLANTS 223 



On Uncultivated Light or Medium Soils. 



Exhausted Per cent remaining in soil unex- 

 Kind of Fertilizer Used (in years) hausted at the end of each year 



Lime 



Bone meal 



Phosphatic guano 



Dissolved bones and plain super- 

 phosphates 



High-grade ammoniates, guanos. 



Cotton-seed meal 



Barnyard manure 



On Uncultivated Pasture Land. 



Exhausted Per cent remaining in soil unex- 

 Kind of Fertilizer Used (in years) hausted at the end of each year 



Lime 



Bone meal 



Phosphatic guano 



Dissolved bone, etc 



High grade ammoniated guanos. 



Cotton-seed meal 



Barnyard manure 



The figures given above are used in fixing the 

 rental for new tenants. In this country no such care- 

 ful estimates have been made. 



Amounts of Nitrogen, Phosphoric Acid, and Potash 

 Found Profitable for Different Crops Under Average 

 Conditions per Acre. 



(Taken Chiefly from New Jersey Experiment Stations Reports.) 



Nitrogen 

 Pounds 



Wheat, rye, oats, corn 16 



Potatoes and root crops 20 



Clover, beans, peas and other leguminous crops 



Fruit trees and small fruits 25 



General garden produce 30 



