overview wetland upland
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Piedmont non-alluvial forests Non-alluvial Forests are isolated wetlands surrounded by terrestrial communities. They are not associated with river floodplains though they may share some wetland species. The uncommon Upland Depression Swamp Forest is found in poorly drained depressions on upland ridges and flats. The Low Elevation Seep community occurs in seepages and springs at the base of slopes or edges of bottomlands.Upland depression swamp forest VA Dept of Conservation & RecreationUpland Depression Swamps The uncommon Upland Depression Swamp Forest is an isolated forested wetland found in poorly drained depressions on upland ridges and flats. It occurs on unusually flat areas with hardpan soils derived from mafic rocks or slates. Habitats include shallow, seasonally rain-flooded upland basins where water stands for part of the year but is not great enough to prevent a closed tree canopy from forming. Sites which hold enough standing water can be important breeding sites for amphibians.
Upland depressions vary in size and are usually dominated by overcup oak, swamp white oak, basket oak or sweet gum. The shrub and herb layers are sparse but typically include greenbrier and sedges.
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Local Sites Low elevation seep VA Dept of Conservation & RecreationCoastal Plain/Piedmont Acidic Seepage Swamps The Low Elevation Seep community occurs in seepages and springs at the base of slopes or the edges of bottomlands. Well-developed seeps contrast sharply with adjacent communities in their abundant wetland vegetation and permanently saturated, mucky soils. Seeps are fairly common and tend to be small, often shaded by the canopy of trees rooted in adjacent communities. Despite a lack of much standing water, seeps are important breeding and foraging sites for amphibians.
Low elevation seeps are distinguished by wetland vegetation including Southern wild raisin, Northern wild raisin, orange jewelweed, cinnamon fern, royal fern, netted chain fern and sedge.
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Local Sites
Piedmont floodplain forests There are several types of floodplain communities in Orange County. The most common, the Alluvial Forest and the Bottomland Forest , are found in stream valleys of various sizes. Standing water is absent most of the time, but regular seasonal inundation and deposition of sediments are characteristic. They usually are lushly vegetated, with an abundance and high diversity of vines, shrubs, and herbs beneath a varied canopy.
Much more uncommon are the Swamp Forest , which is restricted to the Triassic Basin area found only on the easternmost edge of the county, and the Levee Forest , found only at the southwestern corner where the Haw River forms about two miles of the county border.Alluvial forest David Blevins PhotographyMorgan Creek, Mason Farm Biological Reserve The Alluvial Forest occurs in the narrow floodplains of small streams or on large rivers where the floodplain is narrowed by bedrock. These floodplains are too small to differentiate communities by depositional landform. Flooding occurs for shorter periods and is more variable than on the larger floodplains of bottomland forests. The canopy is mixed, including floodplain species, widespread species, and upland species but with widespread species dominating.
Most of the canopy is widespread species such as sweet gum and tulip-tree but characteristic alluvial species such as sycamore, river birch or Southern hackberry are common.
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Local Sites Bottomland forest NC Geological SurveyEno River Geology Destinations: Floodplain deposits Bottomland Forests that are located on the higher parts of large floodplains are flooded for brief to moderate periods during the growing season. These sites occur on terraces, on the higher parts of depositional ridge and swale systems, and on some wide flat floodplains. Natural vegetation is a mix of bottomland oaks, tulip-tree, sweet gum, and sometimes American beech mixed with upland oaks and hickories. Bottomland Forests that are located on lower terraces, ridges, and flat floodplains lack an appreciable number of upland species.
Bottomland Forests vary in composition depending on whether they are close to the river or higher up the floodplain. Oaks are usually a prominent feature and may include willow oak, basket oak, cherrybark oak, overcup oak, water oak and sometimes white oak.
Plant List Detailed Guidesheet
Local Sites Swamp Forest unknown photographer The Swamp Forest is found mainly in the Triassic Basins. Usually located in the wetter parts of large floodplains, prolonged flooding is common and the community is dominated by flood-tolerant species, with a relatively sparse herb layer. While overcup oak is found here, the Swamp Forest is too wet for most other oak species.
The canopy is usually dominated by green ash, American elm, red maple or overcup oak, while the herb layer is generally dominated by sedges, lizard’s tail or false nettle.
Local Sites Levee Carolina Vegetation SurveyLarge River Floodplain and Levee Forests Because Orange County is a headwater region, large streams are lacking. Only at the southwestern corner, where the Haw River forms about two miles of the county border, is there a large enough river system to deposit the sediment volume needed for the development of a Levee Forest community.
Dominated by sycamore, river birch, box elder and southern hackberry, this community occurs only along a narrow portion of the Haw River.
