AMERICAN AGRICULTURE. 



hay are estimated after they have been dried in the air ; the 

 roots as they are taken from the field. The clovers and 

 grass lose from 55 to 75 per cent, of their entire weight 

 when full of sap, lessening of course, as they approach to 

 the state of ripening their seed. The potato loses in drying, 

 69 per cent, of water; the turnep, 91 ; the carrot, 87; the 

 turnep leaf, 86 ; the carrot leaf, parsnep and parsnep leaf, 

 each 81 ; and the cabbage, 93. 



There is much variation in the different specimens of the 

 above substances subjected to examination, according to the 

 peculiar variety, the different circumstances and various 

 stages of their growth. The oat is the most variable of the 

 grains, one specimen sometimes containing three times the 

 quantity of ash afforded by others. The roots also, sometimes 

 vary as three to one in their quantity of ash. As the grain 

 and most of the other crops approach maturity, the quan- 

 tity of some of the principles constituting the ash, lessens, 

 as of potash and soda, their presence being no longer neces- 

 sary in the sap, to aid the formation of the various products 

 of the plants. 



Later and probably more accurate analyses, give consider- 

 able variations in the relative quantities of the elements of 

 the ash of different plants. Thus, an average of six of these, 

 gave of peas with the pod, about 35 per cent, of phosphoric 

 acid, and of beans, about 32 per cent. But the table is 

 given to illustrate principles in the organization of plants, 

 rather than to define the precise relative proportions of the 

 constituents of each. 



The farmer will perceive from this table, the great value 

 of ashes to his crops. The quantity seems small in compari- 

 son with the total weight of the vegetable ; yet small as it 

 is, the aggregate of a few years will so far exhaust the soil 

 of one or more of the principles necessary to sustain a luxuri- 

 ant vegetation, that it will cease to yield remunerating re- 

 turns. The annual exhaustion of salts from large crops of 

 grain, roots and grass, is from 180 to more than 250 Ibs. in 

 every acre of soil. The ashes of vegetables, consist of such 

 elements as are always required for their perfect maturity, 

 and it is evident, they must furnish one of the best saline, 

 manures, which can be supplied for their growth. They 

 are to the earthy parts of vegetables, what milk is to the ani- 

 mal system, or barn-yard manures to the entire crop ; they 

 contain every element, and generally in the right propor- 

 tions, for insuring a full and rapid growth. 



