Southeastern conifer forests

The Southeastern conifer forests are a temperate coniferous forest ecoregion of the southeastern United States. It is the largest conifer forest ecoregion east of the Mississippi River.^[2] It is also the southernmost instance of temperate coniferous forest within the Nearctic realm.

Climate

This ecoregion has a humid subtropical climate with precipitation highest in the warmest months.

Plant communities

Historic vegetation was dominated by open woodlands of longleaf pine (

Southern coastal plain nonriverine cypress domes are small forested wetlands characterized by their dome-shaped appearance, with taller trees in the center and shorter trees around the perimeter. These wetlands occur on poorly drained depressions surrounded by pine flatwoods. Pond cypress (Taxodium ascendens) dominates the canopy, which it shares with swamp tupelo (Nyssa biflora) and sweetgum (Liquidambar styraciflua).^[7]

Oak dome and hammock

The

Southern coastal plain hydric hammocks are found on the flat lowlands of the southern and outermost parts of the coastal plain, usually over limestone substrates. These forests of evergreen and deciduous hardwood trees occur near the floodplains of spring-fed rivers with relatively constant flows. They can be large areas of broad, shallow wetlands. Common trees include Atlantic white cedar (Chamaecyparis thyoides), elm (Ulmus americana), red maple (Acer rubrum), swamp laurel oak (Quercus laurifolia), southern live oak (Quercus virginiana), american sweetgum (Liquidambar styraciflua), sugarberry (Celtis laevigata), and cabbage palm (Sabal palmetto). Dahoon holly (Ilex cassine) is a typical shrub.^{[9] [10]}

Maritime forest

On the Gulf coastal plain, maritime forest consists of a mosaic of forests and shrublands on barrier islands and strands. It occurs in sheltered areas behind coastal dunes and grasslands. Forests are dominated by a mixture of needle-leaved and broad-leaved evergreen trees, including sand pine (

This includes a variety of deciduous oak forests and mixed evergreen forests dominated by oak. Pines are often present as well. This forest is found in fire-sheltered locations surrounded by pine-dominated uplands, including slopes near rivers and sinkholes. Sand laurel oak (Quercus hemisphaerica) is the typical oak species; post oak (Quercus stellata), southern red oak (Quercus falcata), and white oak (Quercus alba) are associates. The forest canopy can be diverse, including hickories and other hardwood species. Common pines include loblolly pine (Pinus taeda), spruce pine (Pinus glabra), or shortleaf pine (Pinus echinata). To the south, this becomes the southern coastal plain oak dome and hammock.^[13]

Mesic slope forest

On the southern Atlantic coastal plain, mesic slope forest is found on steep slopes, bluffs, and sheltered ravines. Fire is rare. They occur on mesic soils, and contain species not found in other forest systems in the area. These include American beech (Fagus grandifolia), southern magnolia (Magnolia grandiflora), and purple anise (Illicium floridanum). The related east Gulf coastal plain northern mesic hardwood slope forest occurs to the north and has more deciduous trees. ^[14]

On the inland east Gulf coastal plain, mesic slope forest consists of deciduous hardwood forests found in slopes and ravines. They inhabit mesic sites between drier uplands and moister streams. American beech (Fagus grandifolia), white oak (Quercus alba), and cherrybark oak (Quercus pagoda) are the distinguishing tree species. Loblolly pine (Pinus taeda) is common in the southern part of the range. The related southern coastal plain mesic slope forest is found to the south.^[15]

Dry and dry-mesic oak forest

These forests occur on dry and dry-mesic sites and are dominated by oaks and hickories. These habitats are protected from fires by either steep topography, isolation, or limited flammability of the vegetation. Typical canopy species include white oak (Quercus alba), sand laurel oak (Quercus hemisphaerica), mockernut hickory (Carya tomentosa), and pignut hickory (Carya glabra).^[16]

Highlands freshwater marsh

Southern coastal plain blackwater river floodplain forests occur in the drainages of blackwater rivers and streams. Typical trees include bald cypress (Taxodium distichum), water tupelo (Nyssa aquatica), and Atlantic white cedar (Chamaecyparis thyoides).^[19]

Fauna

Mature longleaf pine forests are important habitat for the vulnerable red-cockaded woodpecker (

Today, nearly all mature stands of longleaf pine are gone, and only a few isolated sites still contain substantial natural habitat. In many areas, longleaf pine forests have been replaced with plantations of slash pine (Pinus elliottii), which are less biologically diverse than native habitat.

See also

• List of ecoregions in the United States (WWF)

References