Eastern deciduous forest

Description

The great eastern deciduous forest of North America was once an unbroken swathe of imposing trees that stretched from northern New England to central Florida, and west to the Mississippi River ⁽¹⁾. Although it has been subject to intensive human use throughout the years, the eastern deciduous forest is still a diverse and beautiful habitat, supporting an abundance of wildlife ⁽²⁾.

The eastern deciduous forest forms part of one of the major biomes on earth, the temperate deciduous forests ⁽³⁾, which can be found in eastern North America, Europe...

Eastern deciduous forest fact file

• Description
• Range
• Biodiversity
• Threats
• Conservation
• Find out more
• Glossary
• References

Description

The great eastern deciduous forest of North America was once an unbroken swathe of imposing trees that stretched from northern New England to central Florida, and west to the Mississippi River ⁽¹⁾. Although it has been subject to intensive human use throughout the years, the eastern deciduous forest is still a diverse and beautiful habitat, supporting an abundance of wildlife ⁽²⁾.

The eastern deciduous forest forms part of one of the major biomes on earth, the temperate deciduous forests ⁽³⁾, which can be found in eastern North America, Europe, China and Japan ⁽³⁾. Deciduous forests are those dominated by deciduous trees - broad-leaved plants that are ill-suited to enduring the harsh temperatures of winter, and so shed their vulnerable foliage each autumn ^{(4) (5)}.

The eastern deciduous forest is composed of a remarkable diversity of landscapes and ecosystems that differ to some extent in vegetation, soil and wildlife ⁽⁴⁾. Many people divide this huge forest into a varying number of smaller regions ⁽⁶⁾, each being characterised by two or three dominant species ^{(2) (5)}, from the northern hardwood forest in the north, to the oak-hickory and beech-maple forests further south ⁽⁵⁾.

Throughout the eastern deciduous forest, mature trees range in height from 18 to 30 metres ⁽⁶⁾. Rolling hills characterise most of the area, but some parts are nearly flat and the Appalachian Mountain range, which extends from Labrador in Canada to Alabama in the United States, reaches around 900 metres ⁽⁷⁾. A patchwork of fields, wetlands, streams and ponds embellish this landscape ⁽²⁾.

Like all temperate forests, the eastern deciduous forest has cold winters, but mild autumns and springs and long, warm summers ^{(1) (3)}. The average annual temperature is between 4 and 15 degrees Celsius ⁽⁷⁾. Precipitation is highly variable across this extensive region, but is distributed fairly evenly throughout the year. Up to 152 centimetres falls annually in the southern Appalachian Mountains but this drops to less than 76 centimetres where the forest gives way to grassland ⁽⁵⁾. Soils also vary throughout the forest, but in general are highly fertile ⁽²⁾.

Range

The eastern deciduous forest covers almost all of the eastern United States, except for the subtropical vegetation at the southern tip of Florida and an intrusion of grassland known as the prairie peninsula ⁽⁵⁾. It extends from the Atlantic coast as far west as western Minnesota, Iowa and North Dakota, south to Texas ⁽⁶⁾.

To the north, the eastern deciduous forest is bound by the coniferous forests of southern Canada, and to the south by the Gulf coast and subtropical forests of southern Florida. The Atlantic coast clearly marks the eastern edge, while to the west, a landscape of grassland, prairie and extensive farmland separates the eastern deciduous forest from the largely coniferous forest of the western United States ⁽⁴⁾.

Biodiversity

Plants

More than 110 species of tree occur in the eastern deciduous forest, of which about 75 percent are deciduous ⁽⁴⁾. In each region of the forest, different trees dominate ⁽²⁾.

The northern hardwood forest, around the Canadian border, is dominated by yellow birch (Betula alleghaniensis), American beech (Fagus grandifolia) and sugar maple (Acer saccharum) ⁽⁶⁾. Two conifers, eastern hemlock (Tsuga canadensis) and white pine (Pinus strobus) grow abundantly among the broad-leaved species ⁽⁶⁾. In autumn, this region can be the most beautiful, as it turns into a patchwork of reds and oranges ⁽⁶⁾.

In the north-central forest region, often known as the beech-maple forest, American beech (Fagus grandifolia) and sugar maple (Acer saccharum) continue to dominate ⁽²⁾, and can comprise up to 90 percent of the trees ⁽⁶⁾.

The oak-hickory forests are the most common type within the eastern deciduous forest, which is dominated by hickory (Carya species) and a number of oaks including the northern red oak (Quercus rubra) and white oak (Quercus alba) ⁽⁸⁾, the latter of which enjoys one of the widest ranges of any tree species in eastern North America ⁽⁶⁾.

In addition to this, hundreds of wildflowers and other herbaceous and woody species blanket the forest floor ⁽⁴⁾.

Mammals

Around 43 species of mammal occupy the eastern deciduous forest ⁽⁴⁾, the majority of which occur in the northern two-thirds of the region. Most of these are rodents (mice, voles, squirrels), such as the American red squirrel (Tamiasciurus hudsonicus,) and insectivores (shrews and moles) which generally forage on the rich forest floor, and bats, such as the little brown bat (Myotis lucifugus) which forage in and above the forest canopy ⁽⁴⁾.

However, larger mammals can also be found in eastern deciduous forest, such as the American black bear (Ursus americanus) striped skunk (Mephitis mephitis), northern raccoon (Procyon lotor), and the white-tailed deer (Odocoileus virginianus) ⁽⁴⁾.

Birds

About 154 bird species are found in the eastern deciduous forest ⁽⁴⁾. Birds of prey, such as the northern goshawk (Accipiter gentilis) and bald eagle (Haliaeetus leucocephalus) soar over the forest searching for food ⁽⁴⁾, while nuthatches and woodpeckers, such as the northern flicker (Colaptes auratus), forage along tree trunks and large branches, chipping away at the bark in search of food ⁽⁴⁾. The wild turkey (Meleagris gallopavo) may be seen foraging on the ground for acorns, seeds, grains, berries and insects ⁽⁹⁾, while the ruby-throated hummingbird (Archilochus colubris), eastern America’s sole breeding hummingbird, flits through the forest feeding on nectar ⁽¹⁰⁾.

Reptiles and amphibians

Of the 23 species of reptiles that occur in the eastern deciduous forest, most can be found in the southern two-thirds ⁽⁴⁾. The common garter snake (Thamnophis sirtalis) and timber rattlesnake (Crotalus horridus) are characteristic reptiles of this region ⁽⁷⁾.

Around 17 species of amphibians occur in the eastern deciduous forest ⁽⁴⁾, many of which occur in the southern Appalachian Mountains, which contain an impressive diversity of woodland salamander species found nowhere else in the world ⁽⁴⁾. This includes the red-cheeked salamander (Plethodon jordani) which occurs amongst leaf litter on the forested slopes in part of the Appalachian Mountains ⁽¹¹⁾.

Invertebrates

The eastern deciduous forest provides habitat for a wealth of invertebrates ⁽⁵⁾ from the towering heights of the canopy to the leaf litter-covered forest floor ⁽¹⁾. Butterflies, moths and their caterpillars, such as the monarch butterfly (Danaus plexippus) ⁽¹²⁾ and striped hawkmoth (Hyles livornica), provide food for many birds, while the forest’s salamanders prey on beetles, other insects and their larvae ⁽¹⁾.

Threats

Most of the eastern deciduous forest has been logged, burned or cleared for farming at one point over the last two centuries, so very few areas of primary forest, with its wide-trunked and towering trees, remain ⁽²⁾.

Deforestation in eastern North America started in earnest in the 1600s, and migrated westward with agricultural settlement until the mid-1800s ⁽³⁾. Land that was once almost entirely forested, such as Vermont, was more than 80 percent deforested and converted to agriculture ⁽³⁾.

With the industrial revolution, and a shift in economies from rural agriculture to urban manufacturing and technology, large areas of agricultural land were abandoned and are slowly reverting back to forests ⁽³⁾. However, numerous threats to the eastern deciduous forest remain, including air pollution ⁽³⁾ and global climate change ⁽⁴⁾.

Chestnut (Castanea species) was once a dominant, and commercially important, tree in the eastern deciduous forest, but has been virtually eliminated in what has been called one the greatest botanical disasters ^{(3) (5)}. The fungal disease ‘chestnut blight’ was first detected in 1904, after being bought into the region on Chinese chestnut trees ⁽⁵⁾. By 1930 the disease had spread throughout the range of the American chestnut ⁽⁵⁾, and to date, an estimated four billion chestnut trees have died ⁽¹³⁾. Mature chestnut trees became virtually extinct in the 1950s, but as the fungus does not survive in the soil, it does not kill the whole tree, so shoots growing out of decade-old stumps may still be seen ⁽¹³⁾. However, very few of these small sprouts live long enough to flower, and so it is just a matter of time before all the small sprouts die out ⁽¹⁴⁾.

Conservation

The United States is behind only Costa Rica in the percentage of its land set aside for its citizen’s use and enjoyment, as national forests, parks, and wildlife refuges ⁽⁴⁾. Around 50 national forests, 122 national wildlife refuges, and 6 major national parks, including the Great Smokey Mountains National Park, occur in the eastern deciduous forest ⁽⁴⁾, each offering varying degrees of habitat protection. For example, national forests are managed to sustain a healthy ecosystem whilst also addressing people’s need for resources and services ⁽¹⁵⁾, while national parks are restricted from most development, and are focused on animal and environmental protection and human enjoyment ⁽¹⁶⁾.

Recent studies indicate an increase in forest area in North America, as a result of the abandonment of agricultural land ⁽³⁾, a fantastic first step in a long, slow process.

There is even some hope for the American chestnut. The American Chestnut Foundation has planted hundreds of what it hopes could be blight-resistant seeds. They currently appear to be thriving, although whether they are truly blight-resistant will not be known for five years or more ⁽¹⁴⁾.

Find out more

Learn more about forest conservation:

• Earthwatch Institute - North America Regional Climate Centre:
  www.earthwatch.org/europe/rcc_northamerica
• WWF: www.worldwildlife.org/what/globalmarkets/forests/index.html
• Defenders of Wildlife: www.defenders.org/wildlife_and_habitat/habitat/forest.php

Discover more about the American chestnut:

• The American Chestnut Foundation: www.acf.org

Glossary

Biomes

large geographical areas of distinctive animals and plants, which are adapted to that particular environment. Major biomes include deserts, grasslands, tropical forests and tundra.

Coniferous

of or relating to conifer trees, which have evergreen, needle-like leaves and bear cones. Includes pine and fir trees.

Invertebrates

animals with no backbone, such as insects, crustaceans, worms, molluscs and spiders.

Larvae

stage in an animal’s lifecycle after it hatches from the egg. Larvae are typically very different in appearance to adults; they are able to feed and move around but usually are unable to reproduce.

Primary forest

forest that has remained undisturbed for a long time and has reached a mature condition.

References

1. Bambaradeniya, C., Flores, C., Ginsberg, J., Holing, D., Lumpkin, S., McKay, G., Musick, J., Quilty, P., Stonehouse, B., Woehler, E.J. and Woodruff, D. (2009) Illustrated Atlas of Wildlife. University of California Press, Berkeley and Los Angeles, California.
2. Sayre, A.P. (1994) Temperate Deciduous Forest. The Millbrook Press, Connecticut.
3. Reich, P.B. and Frelich, L. (2002) Temperate deciduous forests. In: Munn, T. (Ed.) Encyclopedia of Global Environmental Change. John Wiley & Sons, Chichester.
4. Yahner, R.H. (2000) Eastern Deciduous Forest: Ecology and Wildlife Conservation. University of Minnesota Press, Minneapolis, Minnesota.
5. Bolen, E.G. (1998) Ecology of North America. John Wiley & Sons, New York.
6. Kricher, J. and Morrison, G. (1998) Eastern Forests: A Field Guide to Birds, Mammals, Trees, Flowers and More. Houghton Mifflin Company, New York.
7. Bailey, R.G. (1980) Description of the Ecoregions of the United States. U.S. Department of Agriculture, Miscellaneous Publication No. 1391.
8. Apfelbaum, S.I. and Haney, A. (2010) Restoring Ecological Health to Your Land. Island Press, Washington, D.C.
9. Kaufman, K. (1996) Lives of North American Birds. Houghton Mifflin, New York.
10. Robinson, T.R., Sargent, R.R., and Sargent, M.B. (1996) Ruby-throated hummingbird (Archilochus colubris). In: Poole, A. (Ed.) The Birds of North America Online. Cornell Lab of Ornithology, Ithaca.
11. AmphibiaWeb (April, 2011)
    http://amphibiaweb.org
12. National Geographic (April, 2011)
    http://animals.nationalgeographic.com/animals/bugs/monarch-butterfly
13. DiChristina, M. (1993) Rescuing an American icon. Popular Science, 243: 72-75.
14. American Chestnut Foundation (April, 2011)
    http://www.acf.org
15. U.S. Forest Service (April, 2011)
    http://www.fs.fed.us
16. U.S. National Park Service (April, 2011)
    http://www.nps.gov