IMPORTANT TYPES OF PEAT MATERIAL. 13 



and technical utilization, .should therefore be attached to the profile 

 structure of a peat deposit and to the climatic and geologic differences 

 of peat-land areas. 



The arrangement of types and groups of peat material given be- 

 low is, it should be repeated, a tentative one. It is presented partly 

 from an ecologic point of view and deals, therefore, with a series of 

 peat-forming vegetation units within a set of field conditions such 

 as the writer has described elsewhere for Ohio (5) and Massachu- 

 setts (7). 



The outstanding physical relationship is the water content of the 

 initial area and its effect upon the character of the series of vegeta- 

 tion stages forming peat and upon tlie manner of accumulation of 

 plant remains. This fact is of the greatest importance also from 

 an economic point of view in connection with the improvements to 

 be given a peat-land area. It may be accepted as an axiom that 

 midrained deposits of peat contain about 70 to 95 per cent of water, 

 which should not be reduced to less than 65 per cent if the area is 

 to be used for agricultural crops. Drainage and desiccation of peat 

 materials below 60 per cent of water content have been observed to 

 decrease their capacity for disintegration and weathering. The 

 fibrous organic material becomes brittle, inert, maintains its initial 

 appearance for considerable periods of time, and does not become 

 readily nitrified. Certain of the macerated and water-formed types 

 of peat become hard and compact and are not easily penetrated by 

 the roots of crop plants or by water and air. On the other hand, 

 the dewatering of peat materials, especially the macerated types 

 and the well-disintegrated phases of other types, to a water content 

 of approximately 25 to 30 per cent is an essential requirement be- 

 fore they can be used for technical purposes. Desiccation is one of 

 the outstanding problems in connection with the manufacture of 

 peat into a finished product. Thus far, the employment of pressure 

 or of drying other than by the natural action of sun, air, and wind 

 has not proved economically feasible. 



It is obvious, therefore, that the utilization of peat deposits for 

 agriculture, for manufacturing purposes, or for a combination of 

 both implies operations which appear in some degree antagonistic. 

 They have been harmonized, however, but only through investigations 

 which give information concerning the quality and quantity of peat 

 materials, the conditions of their formation, and the methods of 

 development required before they can be made available sources of 

 food, power, or finished products. On the continent of Europe in- 

 dustries which are dependent on peat materials for these purposes 

 have been centralized and located in the vicinity of selected deposits 

 situated conveniently with respect to cheap water transportation. 

 Provision is made for contemporaneous and subsequent cultivation 



