SOIL EXHAUSTION AND ROTATION OF CROPS. 



179 



state of those which still exist there so that they may become 

 available. 



Chemical science has established the fact that every crop 

 requires a variety of materials to support it. I have here a num- 

 ber of printed sheets, containing a table of the average quantities 

 of the chief ingredients of our ordinary cultivated crops, of which 

 I would like every gentleman present to have a copy. 



Average Quantity of Water, Nitrogen, total Ash and Ash-elements in 

 1000 lbs. of fresh or Air-dry Vegetable Mailer. . 



By Prof. Wolff, of the Agricultural Academy, at llohenheim. 



Wheat, grain 



Wheat, straw 



Rye, grain 



Bye, straw 



Oats, grain 



Oats, straw 



Barley, grain 



Barley, straw 



Indian corn, grain 



Indian corn, stalks and leaves 



Buckwheat, grain 



Uuckwheat, straw 



Meadow hay 



Red Clover hay 



Timothy grass 



Maize fodder, green 



Red Clover srrcen 



Potatoes, tuoers 



Potatoes, tops 



Turnips, roots 



Turnips, tops. 



Carrots, roots 



Carrots, tops 



Hops, entire plant 



Hops, the cones 



Tobacco 



Stablo manure 



Dunghe.ip licjuor 



Feces, fresh 



Urine, human, fresh 



Night soil, f^ces and urine, fresh . . 



Bone dust 



Nitrate soda 



Hulphato ammonia 



E lab. guano 



Ground kelp 





3 



-a 



Jr" 



ra 



0.4 



1 2 

 0.4 

 0.8 

 0.4 

 1.5 

 05 

 1.6 

 0.1 



2 5 

 0.2 

 2.7 

 3.4- 

 1.7 

 0.8 

 0.3 

 04 

 6 

 6 



' 1.1 

 14 

 0.6 

 1.5 

 3.8 

 16 

 7.7 

 2.8 

 0.7 

 0.8 

 0.1 

 4 



ii 



550 



68 



To give an illustration with one of the substances which is 

 absolutely essential for vegetable growth, I will take sulphuric 



