﻿Nichols: The vegetation of Connecticut 193 



Two types of meadows might be distinguished, viz., wet meadows 

 and dry meadows. But the two are not sharply delimited from 

 one another, and it is hardly worth while here to attempt to treat 

 them separately. Owing to their suitability for the growth of 

 grasses, meadows, especially the drier ones, are commonly culti- 

 vated and cut over annually for hay, and much of their natural 

 vegetation is thereby eliminated. 



The shrub stage in a permanent spring swamp closely approxi- 

 mates the corresponding stage in a lake swamp. The tree stage 

 likewise is quite similar, although some of the trees to be mentioned 

 presently as characteristic of periodic swamps frequently occur 

 here also. In periodic spring swamps the shrub stage in the 

 succession scarcely differs from the shrub stage in permanent spring 

 swamps, except for the scarcity or absence of markedly hydro- 

 phytic species like Cephalanthus , the greater abundance of the 

 spiraeas and some others of the less hydrophytic shrubs, and the 

 frequent occurrence of mesophytic shrubs. In northwestern 

 Connecticut Potentilla fruticosa is very characteristic of such areas. 

 But the tree stage in periodic swamps exhibits noteworthy dlfifer- 

 ences as compared with the tree stage in permanent swamps. For, 

 while any of the trees listed as characteristic of permanent swamps 

 may be found here also, and while here as there red maple and elm 

 may be the predominant species, the forests of periodic swamps 

 are characterized by the presence of a number of trees which 

 require an abundant water supply, but which do not thrive well in 

 a permanently saturated soil. Among these may be mentioned 

 Tsuga canadensis, Carya cordiformis, Carpinus caroliniana, Quercus 

 bicolor, Quercus palustris, Liriodendron Tulipifera, Nyssa sylvatica, 

 Fraxinus pennsylvanica and Platanus occidentalis. The herbaceous 

 vegetation of such swamps includes species which are seldom found 

 in permanent swamps, such as Erythronium americanum, Dentaria 

 diphylla, and Panax trifolium. 



As concerns the building up of the substratum to a higher level 

 through the accumulation of plant remains, a state of equilibrium 

 somewhat analogous to that observed in many lakes is very com- 

 monly encountered in clayey or sandy swamps where, for various 

 reasons, dead organic matter oxidizes so rapidly that humus fails to 

 collect. Particularly is this true of periodic swamps. In a colder, 



