(salt water) has moved in over the area. I did quite a bit of 

 boring and found the typical bog peat now being covered with 

 peat that is of the Phragmites type. This is a succession 

 going in the other direction. 



Chapman: I was going to say this is a succession going in the other di- 



rection as a direct result of the relative rate of the subsidence 

 of the land in relation to the rate of accretion, and you can get 

 it, I agree, on this coast particularly. I can give you ex- 

 amples of it from Massachusetts southward, of salt marsh 

 overlying fresh water peats or even forest swamps. 



Redfield: Well now, if you had a salt marsh, as I have frequently seen 



them, where a flood or some accidental cause has spread a 

 thin layer of sand over the surface, killing the existing veg- 

 e tation, then would there not be a succession? There w^ould 

 be certain plants which would arrive first. I would suspect 

 Salicornia in our marshes and then later the grasses would 

 get in very much as in an old field. There is a succession of 

 forms which gradually penetrate and it turns into a forest. 



Chapman: Well that, of course, is a different situation altogether because 



there, as a result of the flooding and the breaking of the dikes, 

 you are killing an existing mesophytic vegetation and starting 

 over again. Where you start, I think, depends on the level of 

 your existing mesophytic vegetation in relation to the sea level 

 at the time when the dikes are broken. Again there are num- 

 erous examples of that throughout the world. This secondary 

 succession developing in killed mesophytic areas. 



Burbanck: Is the case a special one on the Cape where again and again 



I find that Typha is spread all around over the Spartina ? 

 Many of the Spartinas grade into Typha but then they break 

 off during the fall and winter and there are great accretions, 

 great piles of the Typha spread all over the tops of the 

 Spartina and as the Spartina germinate they come up through 

 them. This adds a substantial amount of material to the 

 marsh. 



Chapman: Well, I think that is part and parcel of the transition to the 



fresh water marsh stage because that accumulation of organic 

 material is going to raise the level of the plant in relation to 

 the underlying water table obviously and mesophytic plants 

 will be able to come in under those circumstances and Typha 

 is another one of the reed swamp species which does take 

 part in the transition. I have certainly seen Typha -mangrove 

 in Jamaica giving way to Typha domingensis (Pers) swamp 

 and 1 believe that there is the transition to the fresh water 

 swamp that you have in the mangrove there, but I agree that 



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