ORGANIC ELEMENTS : MANl' RES AND CRCPS. 



WHEAT STUBBLE. 



From 120 square yards of ground we have obtained 13 lbs. of 

 Btubble dried in the air. The same isurface in another field produced 

 171 lbs. 



Thus we have 5| cwts. of stubble per acre ; but as wheat recurs 

 twice in the rotation, the residues must be doubled ; say, IH cwts. 

 Stubble loses 0.26 of moisture when dried completely at 230°. 



In 1839, the wheat after the drilled crop, or £tfter clover, was onlj 

 17 bushels per acre. 



I have assigned to stubble the same composition as that of straw. 



CLOVER ROOTS. 



A surface of 120 square yards gave 44 lbs. of roots, vveighed after 

 being thoroughly dried in the sun ; when pulverized after drying in 

 the stove the weight was reduced to 37 lbs. 



3 oz. 4 dwts. of powdered roots lost by drying, at a temperature 

 of 230° F., 5 dwts. of moisture. Thus the 44 lbs. of roots dried in 

 the sun would have weighed 34 lbs., and one acre would have 

 furnished I2f cwts. of residue perfectly dry. 



In 1839, the clover crop when reduced to hay was far below the 

 average. 



COMPOSITION OF THE ROOTS. 



Carbon 434 



Hydrogen 5.3 



Oxygen 36.9 



Azote L8 



Salts and earth 12.6 



100.0 



OAT STUBBLE. 



The residue of the oat crop, which concludes the rotation coarse, 

 does not act upon the present, but on the next rotation ; in the same 

 way as the organic remains left in the ground by the oats which ter- 

 minated the antecedent course, exerted their influence upon the 

 present one. In 1839, the oat crop was above the average ; it was 

 as high as 16 cwts. 2 qrs. 18 lbs. per acre. 



One French are of the land, equal to 120 square yards English, 

 yielded 20 lbs. of stubble dried in the air, or at the rate in round 

 numbers of 8 cwts. per acre. 



In the following table I have given a srimmary of the results above 

 stated, combining therewith the quantity ind the comi>osition of the 

 manure expended in the rotation. 



