﻿192 Nichols: The vegetation of Connecticut 



Succession in Spring Swamps. — Many swamps have arisen 

 through the filHng in of lakes and ponds in the manner described. 

 But a large proportion of Connecticut swamps, as already pointed out 

 (pp. 173-175), owe their origin to the relation between topography 

 and ground water level. The former type of swamp has been 

 referred to as a lake swamp. In contrast to this, the latter type of 

 swamp, by reason of the fact that its existence depends on the 

 presence of seepage or spring water, may be called a seepage or 

 Spring Swamp. In a spring swamp there of course are never any 

 truly aquatic stages in the succession. Terrestrial plants are 

 present from the very outset. In a Permanent Spring Swamp 

 the pioneer association is commonly dominated by sedges, rushes, 

 and grasses, and in general its composition conforms closely to 

 that described for the sedge stage of the lake-swamp succession. 

 But in a Periodic Spring Swamp the pioneer association may be 

 quite different, both floristically and in its general aspect, from 

 that of a permanent swamp. To be sure, many of the plants 

 characteristic of permanent swamps are represented here also, 

 but on the whole the vegetation is much more mesophytic. Per- 

 haps as good an illustration of a periodic swamp as can be selected 

 is afforded by a Low Meadow. Such an area may be very wet in 

 winter and spring, but later in the season the surface layers of 

 the soil usually become relatively dry. As in permanent swamps, 

 the predominant vegetation here is grass-like, but many other 

 herbaceous plants are also conspicuous. The list of species given 

 below may be considered as fairly representative of meadows. 

 Agrostis alba Gentiana crinita 



Anthoxanthum odoratum Glyceria nervata 



Calamagrostis canadensis Juncus effusus 



Carex lurida Poa pratensis 



Carex scoparia Rhexia virginica 



Carex stellulata Rynchospora glomerata 



Carex stipata Sanguisorba canadensis 



Carex stricta Selaginella apus 



Castilleja coccinea Thalictrum polygamum 



Cyperus strigosus Verbena hastata 



Eupatorium perjoliatum Vernonia noveboracensis 



Eupatorium purpiireum Veronica virginica 



