MASSACHUSETTS PEAT LANDS ■ 35 



(1) The composition of the horizontal and of the vertical strata 

 of peat materials ; 



(2) the degree of disintegration, which is (likewise) dependent 

 on (a) the character of plant associations that contributed to the 

 deposit originally as well as at the present moment, and (b) the 

 duration and eflfectiveness of drainage, the weathering processes 

 and bacterio-fungal agencies under the existing field conditions; 



(3) the shrinkage of the peat materials in relation to the water 

 table to be established by drainage measures; 



(4) the permeability of the materials for water, air, and roots of 

 crop plants; 



(o) the water content of the surface layer of peat soils when under 

 certain crops. 



II. The influence of climate. 



Varied questions are raised by a consideration of the climatic 

 factor combined with others due to the change in field conditions, 

 in peat materials which partly accompany the sequence of peat 

 forming vegetation, in the injfluence of weathering or leaching proc- 

 esses, or in the distribution of rainfall and variations in ground 

 water table affecting peat lands. 



The annual rainfall in the New England states ranges from 40 

 to 50 inches, the greater amount of which is precipitated during 

 winter and in the cooler months of spring and autumn. This 

 condition does not compensate for the loss by evaporation during 

 the drier summer season and hence a more or less variable water 

 level exists upon some peat lands lacking barriers than would be 

 possible if the greater precipitation occurred within the warmer 

 season of the year. On the other hand a relatively high and perma- 

 nent stand of water prevails upon peat lands with natural ridges 

 or with low gradient and where dams have been built or ditches 

 have been neglected. The special climatic conditions under which 

 Massachusetts peat lands have been forming render those with 

 fluctuating changes in the water table and those with subterranean 

 springs in need of more detailed study. 



There impresses itself upon the observer a condition in the soil 

 of certain uplands adjoining peat basins, the character of which 

 deserves much thorough investigation. It is strikingly unlike 

 anything observed in regional peat lands of a more continental 



