IS ROTATION OF CHOPS. 



, 



Ingredients of the soil 



By a crop of Beetroot* (roots without leaves) - 399*6 " 



" " Peas (peas and straw) 618*0 " 



"Rye 284*6 " 



" " Helianthus tuberosus 660*0 " 



These numbers express the quantities of inorganic substances 

 removed from the same soil by different plants, and carried away 

 with the crops. They, therefore, prove that different plants take 

 up into their organism, unequal weights of these ingredients of 

 the soil. It is shown by a further consideration of the composi- 

 tion of these ashes, that they differ essentially from each other 

 with respect to their quality. 



One thousand parts of beet, turnips, or potatoes, yield by in- 

 cineration 90 parts of ashes; the latter are easily fusible, and, 

 contain a large quantity of carbonate of potash, and of salts with 

 alkaline bases. Of these 90 parts, 75 parts are soluble in cold 

 water. 



Two thousand parts of dry fern yield also 90 parts of ashes ; 

 but of these 90 parts none, or only a trace, is soluble in water 

 (Berthier). 



The ashes of wheat, barley, pea, and bean straw, differ in like 

 manner in their composition. Equal quantities of their ashes 

 contain very unequal amounts of ingredients soluble in water. 

 There are certain ashes of plants wholly soluble in water; 

 others are only partially soluble, while certain kinds yield only 

 traces of soluble ingredients. 



When the parts of the ashes Insoluble in water are treated 

 with an acid (muriatic acid), this residue, in the case of many 

 plants, is quite soluble in the acids (as for instance the ashes of 

 beet, turnips, and potatoes) ; with other plants, only half the 

 residue dissolves, the other half resisting the solvent action of the 



* In the above five-yearly rotation, wheat was introduced twice. In the 

 second year the crop of wheat removed from the soil 371 lbs. and in the 

 fourth year 45S lbs. of inorganic substances. This difference depends upon 

 the unequal quantities of straw and corn in the crops of the two years. 

 The weight of the straw and corn of one year was 8790 lbs., in the other 

 year it amounted to 10,858 lbs. The relative proportion of their ashes is 

 exactly the same. 



