Eastern deciduous forests

Eastern deciduous forests
Name	Eastern deciduous forests
Biome	Temperate broadleaf and mixed forests
Countries	United States; Canada

Eastern deciduous forests are a temperate broadleaf and mixed forest ecoregion spanning much of the eastern United States and adjacent Canada. The region interfaces with numerous Great Lakes shorelines, Appalachian Mountains ranges, and coastal plains influenced by the Gulf of Mexico, Atlantic Ocean, and continental air masses. Historically mapped by scientists associated with the U.S. Forest Service, Canadian Forest Service, and ecologists from institutions such as the Smithsonian Institution and Yale School of Forestry & Environmental Studies, these forests have been the focus of conservation efforts by organizations including the Nature Conservancy and World Wildlife Fund.

Overview and extent

The ecoregion stretches from southern Ontario and Quebec through the northeastern United States including New England, across the Mid-Atlantic United States and Ohio River Valley into the Upper South and parts of the Southeastern United States, bordering the Prairies and Piedmont physiographic provinces. Major physiographic features within the extent include the Allegheny Plateau, Blue Ridge Mountains, Shenandoah Valley, and the floodplains of the Mississippi River tributaries such as the Tennessee River, Ohio River, and Susquehanna River. Mapping and classification have been refined through work by the World Wildlife Fund ecoregion framework, the Environmental Protection Agency ecoregions, and historical surveys by the U.S. Geological Survey.

Climate and soils

Climate across the region varies from humid continental in the northern reaches near Montreal and Boston to humid subtropical toward Atlanta and Charlotte, influenced by the North Atlantic Oscillation and seasonal shifts associated with the Gulf Stream. Precipitation is relatively evenly distributed, with snow regimes important in places like Vermont and Maine and thunderstorm-driven rainfall common in the Tennessee Valley and Carolinas. Soils derive from varied parent materials including glacial tills deposited during the Wisconsin glaciation, alluvium in river valleys such as the Hudson River floodplain, and residuum on slopes of the Appalachians, producing alfisols, ultisols, and inceptisols that support diverse hardwood assemblages documented by studies from Cornell University, University of Michigan, and Duke University.

Flora and vegetation communities

Vegetation ranges from mixed mesophytic forests described by early botanists at Harvard University Herbaria and collectors associated with the Royal Society to oak–hickory woodlands, maple–beech–birch stands, and southern pine pockets. Dominant canopy species include genera represented in collections from the New York Botanical Garden and Royal Botanic Gardens, Kew such as oaks (Quercus alba, Quercus rubra), maples (Acer saccharum, Acer rubrum), beeches (Fagus grandifolia), hickories (Carya tomentosa), and tulip poplar (Liriodendron tulipifera). Understories feature shrubs and herbaceous layers studied by botanists at Missouri Botanical Garden, including species used in restoration projects by the U.S. National Arboretum and seed banks like the Millennium Seed Bank Partnership.

Fauna and ecological interactions

Faunal assemblages documented in field studies by researchers at Smithsonian National Museum of Natural History, American Museum of Natural History, and Royal Ontario Museum include large mammals such as Odocoileus virginianus (white-tailed deer), carnivores historically including Ursus americanus and Canis lupus populations once reduced by 19th–20th century policies, and mesopredators like Procyon lotor and Vulpes vulpes. Avifauna includes migratory species tracked by the Audubon Society, Cornell Lab of Ornithology, and Bird Studies Canada such as warblers, thrushes, and raptors using Mississippi Flyway corridors. Invertebrate and fungal interactions documented by mycologists linked to Royal Botanic Gardens, Kew and entomologists at the Smithsonian Institution underpin decomposition, pollination, and trophic dynamics observed across forest types.

Disturbance regimes and succession

Natural disturbances range from windstorms studied after events like Hurricane Katrina and Hurricane Sandy to ice storms and periodic fire regimes historically maintained by Indigenous burning practices associated with cultures recorded in archives at the National Museum of the American Indian. Disturbance ecology research from Yale University, University of Minnesota, and the U.S. Forest Service describes successional trajectories from early-successional aspen and birch stands to late-successional beech–maple forests, often mediated by deer herbivory documented by National Audubon Society and invasive pests like the emerald ash borer.

Human history, land use, and conservation

Human impacts span pre-Columbian land management by peoples documented in collections at the Smithsonian Institution to colonial-era clearing associated with settlers documented in records at the Library of Congress and National Archives. Industrialization, agriculture expansion described in studies at Iowa State University and urbanization in metropolitan regions such as New York City, Chicago, and Philadelphia reshaped forest cover, prompting conservation policy responses including the creation of Yellowstone National Park-era inspirations, the establishment of state forests, National Forests in the eastern United States, and land trusts like The Trust for Public Land and the Land Trust Alliance.

Threats and restoration efforts

Contemporary threats cataloged by the Intergovernmental Panel on Climate Change and regional agencies include climate change impacts, invasive species such as Lonicera maackii and Phragmites australis, pathogens like Cryphonectria parasitica and insect pests including Agrilus planipennis, alongside fragmentation from transportation corridors like the Interstate Highway System and urban sprawl centered on metros such as Boston and Atlanta. Restoration and management initiatives conducted by institutions including The Nature Conservancy, National Park Service, U.S. Fish and Wildlife Service, and academic partners at University of Pennsylvania emphasize reforestation, invasive control, assisted migration trials, and community-based conservation models showcased in programs funded by the National Science Foundation and philanthropic foundations like the Kresge Foundation.

Category:Forests of North America