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What
is a Wetland?
Inland
Wetlands
Where
are all the Wetlands?
Wetlands
for the Future
People
and Wetlands
Classroom
Activities
Facts
Links
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PALUSTRINE
WETLANDS
Palustrine wetlands
include all inland wetlands except those along lakeshores and rivers.
Generally, they are small in size and shallow. Palustrine wetlands
may be connected by surface or groundwater to rivers or lakes; or
they may be isolated.
Forested palustrine
wetlands occur in areas with abundant moisture, such as in the mountains.
In the Rockies, look for them on the west side of watershed divides.
For example, forest wetlands occur more frequently on the Idaho
side of the Bitterroot Mountains, which receive more precipitation
than the Montana side.
When you are
driving, you can easily bypass forest wetlands. They feature tall
trees, an understory of shrubs or younger trees, and often have
plenty of groundcover—similar to the surrounding forests. But
if you walk into a forest wetland, your senses will detect the difference.
The air is often cooler, the ground damp if not soggy. Ferns and
mosses may be abundant, and other understory plants thicker. In
Idaho, forest wetlands provide habitat for several species of salamanders,
toads, and several frogs.
The Coeur d'Alene
salamander exists only in moist forest areas of northern Idaho where
rocky areas meet the wetlands.
In the eastern
United States, moisture loving trees such as red maple, black gum,
Atlantic white cedar, and bald cypress grow in forested wetlands.
In the western
United States, look for tamarack, western redcedar, and western
hemlock. More open wetlands, such as sloughs, feature many kinds
of grasslike plants such as sedges, bulrushes, cattails, and reeds.
Isolated
Wetlands
When a wetland is not connected by surface water to rivers, lakes,
or streams, it is considered an isolated wetland. Examples include
prairie potholes, playas, and vernal pools. Playas exist in the
dry country of northern Texas and eastern New Mexico.
Often surrounded
by irrigated agricultural land, playas are shallow depressions that
hold water usually for only a few weeks or months. During their
brief wet period, playas contribute to groundwater recharge and
provide essential winter habitat for waterfowl-second in importance
only to the Gulf Coast.
Vernal pools,
also called ephemeral ponds, typically are wet in the spring after
snowmelt or seasonally heavy rains. Their shallow, quickly disappearing
waters cannot support fish, thus they provide essentially predator-free
breeding areas for amphibians. Some scientists estimate that half
of the amphibians in the U.S. breed only in these and other seasonal
wetlands.
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