1l' The Relation of the Atmosphere to Agriculture. 



THE RELATION OF THE ATMOSPHERE TO 

 AGRICULTURE* 



By FRANK T. SHUTT, M.A., F.I.C., Chief Chemist, Dominion Experimental Farm 



The fundamental principle to realize in the consideration of this 

 question is that plants are living organisms, and as such, in order to 

 develop and multiply, require food. Their requirements may be 

 ascertained by several methods, chief among which is chemical analysis, 

 by which also we arrive at the proximate and ultimate composition of 

 plant constituents. 



A preliminary analysis of a plant, as for example the Tndian Corn, 

 enables us to arrange its constituents under one or another of the 

 following classes : 



WATER, 



ORGANIC MATTER, 



MINERAL MATTER or ASH. 



Taking as an illustration the Indian Corn plant, when approaching 

 maturity, we find that it is made up of, 



WATER 72.O lbs. 



ORGANIC MATTER 26.6 " 



MINERAL MATTER or ASH 1. 4 " 





IOOO 

 These materials have been derived and assimilated ':>. the plant from 

 two sources, the atmosphere and the soil. 



With respect to the water contained in a plant, it is only necessary 

 to point out that its source is soil-moisture, derived by the deposition of 

 atmospheric aqueous vapour (chiefly rain), and that it has been taken up 

 by the plant roots. 



The mineral constituents are also soil-derived. To be assimilated 

 they must be in solution, and to this end atmospheric agencies and 

 small quantities of acid exuded by the plant rootlets, assist. 



The organic matter of plants is composed of varying quantities of 



Note.- This is idensed report of an address delivered before the Central 



Experimental Farm Club, March 27th, 1S95. 



