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

countered (Table 3.3). The herb layer in zone I1 red
maple swamps may be quite diverse. Common
ferns include cinnamon fern, sensitive fern, royal
fern, marsh fern, ostrich fern, interrupted fern,
crested fern (Dryopteris clistata), and spinulose
woodfern. Skunk cabbage, marsh marigold, false
hellebore, spotted touch-me-not, wild sarsaparilla,
swamp jack-in-the-pulpit, lizard's tail (Saururus
cernuus), smartweeds (Polygonurn spp.), sedges
(e.g., Citrex crinita, C. lurida, and C. stricta),
goldthread, blue bead-lily (Clintonia borealis), and
white clintonia (C. unbellulata) are common
herbs. Species such as water avens (Geum rivale),
maidenhair fern (Adiantum pedatun), and foamflower
(Tiarella cordifolia) are indicative of moderate-
tr, high-base status.
Zone 111. St. Lawrence Valley and Lake
Champlain Basin
Champlain (e.g., IVLissisquoi River delta and Sandbar
Swamp), and red maple-black ash swamps,
W e Floodplain Swamps
Lake floodplain swamps are characterized by a
red maple-silver maple-swamp white oak association,
which is distinctly different from floodplain
forests found along major rivers in Vermont. River
floodplain forests are composed largely of silver
maple, eastern cottonwood, sycamore, and butternut
O[?lompson 1988). Silver maple dominates that
part of the lake floodplain forest nearest the edge
of Lake Champlain, and red maple predominates
toward the landward edge. In the middle, both
species are present, and dominance alternates locally.
A hybrid maple, known as Acer X freemanii,
has been identified in this intermediate zone; it
displays characteristics of both red maple and silver
maple ON. Countryman, Northfield, Vt., - wrsonal
communication). The open shrub layer of the
lake fkoodplain swamps frequently includes mountain
holly and buttonbush (Cephalanthus occidentalis).
A fern-dominated herb layer includes such
species as sensitive fern, interrupted fern, and
cinnamon fern. About 30 species of trees and
shrubs have been documented in these swamps
Zone 111, which coincides with the St. Lawrence
Wley physiographic region in New York and Vermont
(Fig. 3.10), falls almost entirely within the
white pine-hemlock-hardwood forest region
(Fig. 1.3). Both upland and wetland foresk in the
eastern portion of this zone are strongly influenced
by the moderating effect of Lake Champlain on
local climate (Bray 1915). Little published informa- (Vogelmann, personal communication).
tion on red maple swamp communities is available
rZed Maple-Black Ash Swamps
for this area. Floristic data for the New York portion
of this zone are derived primarily from Vosburgh This second major red maple swamp association
(1979) and National Wetlands Inventory (NWI) is found in nonfldplain areas throughout zone
field notes (US. Fish and Wildlife Service, National 111. Bray (1915) described this comunit~ which
Wetlands Inventory? Newton Corner, Mass,). Descriptions
of Vemont forested wetlands in zone 111
are derived mainly from Vosburgh (1979), the Vermont
Natural Heritage Program (VNEB), NWI
field notes, and personal communications.
Along the shores of Lake Champlain, forested
wetlands are found on poorly drained deltas and in
drowned river valleys. Red maple swamp associatiorls
also occur in poorly drained depressions on
the her
floodplain of creeks, behind natural levees
(H.W. Vogelmann, University of Vermont,
Burlington, personal communication). These
swamps are com~only underlain by alluvium that
overlies glaciolacustrine and glaciofluvid deposits.
Outside of the Lake Ci~amplain basin, red maple
swamps are found along upland drainageways and
in isolated basins in both till and stratified drift.
Zone I11 supports two distinct red maple swamp
communities: lake floodplain swamps, which are
commonly found on the eastern shore of Lake
is designated by the Society of American Foresters
as the black ash-elm-red maple forest cover type
(SAF type no. 39; Eyre 1980), as a climax wetland
forest ranging from the lower Hudson River valley
north to the Champlain valley. It predominates
from the northern edge of the Adirondack Mountains
to the Canadian border as well. Part of the
Cornwall Swamp along Otter Creek in Addison
County, Vt., has been considered a classic example
of this forest cover type (Goodwin and Niering
1975). The decline of American elm prompted the
Vermont Natural Heritage Program to classify
these forested wetlands as the red maple-black
ash natural community (Thompson 1988). Dominated
by red maple, black ash, and, to a lesser
extent, American elm, these swamps also support
white pine, gray birch, paper birch (Betulapapyrifera),
green ash, yellow birch, hemlock, northern
white cedar, quaking aspen (PopukLs tremuloides),
tamarack, and balsam fir. Swamp white oak and