Ecology of Red Maple Swamps in the Glaciated Northeast: A ...

ences in nutrient levels, which were influenced by
topographic position and hydrology.
The most common type of red maple swamp
encountered in the Damman and Kershner (1977)
study was the Symplocarpus foetdus-Acer rubrum
community that typically occurs in valley
bottoms where soils are very poorly drained and
fed by groundwater seepage (Fig. 4.1). These
swamps are usually drained by a stream, so that
surface water does not persist for long periods. If
groundwater inflow is especially abundant and
nutrient-rich, a Symplocapus-Acer rubrum-
Ranunculus septentrionalis community is often
found. Distinguishing species, besides swamp
buttercup, in this floristically rich community include
swamp saxifrage, bulbous bittercress, and
golden ragwort. Upslope from the Symplocarpus-
Acer rubrum community, in areas where soils are
poorly drained but surface water is rarely present,
a Betula alkghuniensis-Acer rubrum-Osmunda
cinnamomea community is commonly found
(Fig. 4.1).This transitional community frequently
forms only a narrow belt at the bases of slopes; it
is slightly drier and poorer in nutrients than the
other two types of red maple forests.
Pn devising a floristic classification for wetlands
in the gneissic-schistose bedrock region of northwestern
Connecticut, Messier (1980) also underscored
the link between water regime and nutrient
levels. He observed that, for a given nutrient
regime, the type of wetland community was
closely related to the elevation and degree of fluctuationof
the water table. Figure 4.2 compares the
extent of water level fluctuation during a single
year among five red maple swamp communities
and five other wetland types he encountered. In
reviewing the following findings, remember that
the extent of water level fluctuation may vary
widely among years, even within the same swamp
(Fig. 2.7).
The Osmunda cinnarnomeu-Acer swamp occurred
on peat soils of the valley floor, unlike the
sloping sites described by Damman and Kershner
(1977), and had a saturated water regime. The
water table remained within 10-15 cm of the surface
throughout the growing season, but surface
water was present only briefly. The Rhododendron
viscosum-Acer community occurred both in valley
basins, where groundwater inflow was presumed
to occur, and in basins farther upslope, which were
perched above the local groundwater table. Water
Quercus prinus - rubra
Quercus !11ofoba
and
emsed bedr~ck
I
Fraxlnus Carya
Fraxtnus-Acer saccharu
Befula-Acer rubrum
Fig. 4.1. Topsequences of plant communities on a till-covered gneiss hill in western Connecticut (after Damman
and Kershner 1977). Left side of diagram represents normal topsequence; right side is that of certain
south-facing slopes. Wetland communities are marked with an usterisk. Elevation of summit is between 350 and
400 m above sea level.