A tree is a large woody plant with one main stem, or trunk, and many branches that lives year after year. A forest is a large number of trees covering at least 25 percent of the area where the tops of the trees, called crowns, interlock forming an enclosure or canopy when the trees mature. Deciduous (dee-SID-joo-uhs) forests primarily consist of deciduous trees, such as oaks, basswoods, and elms. Deciduous trees lose their leaves during cold or very dry seasons, as compared to evergreen trees that keep their leaves year-round, usually for several years at a time.
Temperate deciduous forests grow in areas with cold winters and warm summers. They are generally found in the Northern Hemisphere, the southern most part of South America, and New Zealand. These forests are located primarily in the Great Lakes region and the eastern half of the United States, parts of central and western Europe, parts of Russia, and parts of Japan and China. Tropical deciduous forests grow in areas around the equator where the weather is warm, such as the western coast of Chile and South Island, New Zealand. There are two types of tropical deciduous forests—those that grow in dry climates and those that grow in moist climates. Dry climate forests occur primarily in central India; parts of Brazil; and on the African continent from Angola to Tanzania, northward to the Sudan, and over much of West Africa. Moist climate forests are found primarily in northeastern Australia, eastern India, and parts of Burma, Thailand, and Indonesia.
Forests evolved during Earth’s prehistoric past. Since then, all forests have developed in essentially the same way, by means of a process called succession.
The first forests
The first forests evolved from ferns, clubmosses, and other prehistoric plants that, over time, adapted to the surrounding environment and grew more treelike. Trees that preferred a warm, humid,
|WORDS TO KNOW|
|Angiosperms : Trees that bear flowers and produce their seeds inside a fruit; deciduous and rain forest trees are usually angiosperms.|
|Conifer : A tree that produces seeds inside cones.|
|Consumers : Animals in the food web that eat either plants or other animals.|
|Decomposers : Organisms that feed on dead organic materials, releasing nutrients into the environment.|
|Food web : All of the possible feeding relationships that exist in a biome.|
|Gymnosperms : Trees that produce seeds that are often collected together into cones; most conifers are gymnosperms.|
|Mesophytic : Term used to describe a forest that grows where only a moderate amount of water is available.|
|Producers : Plants and other organisms in the food web of a biome that are able to make food from nonliving materials, such as the energy from sunlight.|
|Succession : The process by which one type of plant or tree is gradually replaced by others.|
|Tannins : Chemical substances found in the bark, roots, seeds, and leaves of many plants and used to soften leather.|
tropical climate developed first, followed by those adapted to drier, cooler weather. The first deciduous trees evolved about 145 million years ago, during the latter part of the Cretaceous period in the Mesozoic Era.
About 1 million years ago during the great Ice Ages, glaciers (slow-moving masses of ice) covered about one-third of the land surface of Earth. Eventually, the glaciers retreated, but not before they had destroyed many of the world’s forests and scoured the land of plants. Roughly 12,000 years ago, trees began to repopulate the land that had been covered by ice. In some areas, spruce, larch, ash, and birch trees were among the first species to make a comeback, preparing the way for other trees.
Trees compete with one another for sunlight, water, and nutrients, thus a forest is constantly changing. The process by which one type of plant or tree is gradually replaced by others is called succession. During succession, different species of trees become dominant as time progresses and the environment changes. Succession began following the last Ice Age, and continues today. Succession can occur naturally, when different species of trees become dominant as time progresses and the environment changes. It can also occur from natural disasters, such as forest fires.
Primary succession usually begins on bare soil or sand where no plants grew before. When the right amounts of sunlight, moisture, and air temperature are present, seeds begin to germinate (grow). These first plants are often made up of mosses, grasses, and forbs (a nonwoody broad-leaved plant). They continue to grow and eventually form meadows. Over time, and as conditions change, other plants begin to grow such as shrubs and trees. These plants become dominant and replace or take over where grasses and forbs originally grew.
As primary succession continues, pioneer trees (in some cases birch, pine, poplar, and aspen) begin to thrive. These are tall, sun-loving trees, and they quickly take over the meadow. They change the environment by making shade. This allows trees with broader leaves that prefer some protection from the sun, such as red oaks, to take root. If conditions are
right, a mixed forest of sun-loving and shade-loving trees may continue for many years before more changes occur.
The climax forest
Seedlings from pioneer trees do not grow well in shade; therefore, new pioneer trees do not grow. As the mature trees begin to die from old age, disease, and other causes, the broad-leaved trees become dominant. The shade from these broad-leaved trees can be too dense for their own seedlings too. As a result, seedlings from trees that prefer heavy shade, such as beech and sugar maple, begin to thrive and dominate the forest. These trees produce such deep shade that only those trees or plants that can survive in complete shade will succeed. When this happens, the result is a climax forest—one in which certain species of trees characteristic of the ecological conditions of an area are dominant.
Few true climax forests actually exist because forests are dynamic ecosystems and changes take place that interfere with a forest’s stability. Fires, floods, high winds, and people can all destroy a single tree to acres of trees. Glaciers can mow them down; volcanoes can smother them with ash or molten rock or knock them over with explosive force. Then the process of succession starts over.
Land stripped of trees will eventually be covered with them again if left alone. This is called secondary succession and can take place more quickly than primary succession. Seeds from other forests in neighboring regions are blown by the wind or carried by animals to the site. Soon, the seeds take root and seedlings sprout, and the process begins again.
Deciduous forests are broadly classified according to the climate of the region in which they grow—temperate, dry tropical, or moist tropical.
Temperate deciduous forest
Temperate climates are moderate, and temperate deciduous forests can be categorized in terms of the species of trees that are most common. The following three types are common in North America, and similar species predominate in Europe and Asia:
- Beech-maple: American beech and sugar maple forests mixed with some conifers (trees bearing cones) are found in the southern Great Lakes region, in New England, and in southeastern Canada.
- Oak-hickory: In the southern United States, oaks, such as white oak and chestnut oak, are dominant. Farther west, red oak and black oak are mixed with hickory.
- Mixed mesophytic: Mesophytic means a forest that requires only a moderate amount of water, such as forests in the Appalachian Mountains. Mixed mesophytic forests can be dominated by any of ten or more species of trees, such as buckeye, magnolia, birch, ash, black cherry, sugar maple, and scattered evergreen conifers such as hemlock and white pine.
Dry tropical deciduous forest
Dry tropical deciduous forests occur in regions with long, severe dry seasons, such as the savannas (grasslands) of Africa. The tallest trees are shorter and more twisted than those in a temperate forest, and the bark is thicker. Some trees may store water in their trunks. During the dry season, the trees lose their leaves and many produce flowers. Some, such as wattle trees in Australia, have adapted by producing thorns instead of many leaves.
This Land is My Land
Life in the forest is a constant struggle for food and living space, even among the trees. All around the foot of almost any tree are the seedlings of other trees, ready to take over the space if they can. Some trees have evolved ways to fight back. The black walnut, for instance, has a powerful poison in its leaves, roots, and nutshells. This poison kills the roots of any plants trying to grow in the same soil. Even if the tree is removed, the poison remains in the soil for a long time.
Moist tropical deciduous forest
Moist deciduous forests are found in tropical regions where both rainy and dry seasons occur during the year. These forests are different from tropical rain forests in that the trees, including teak and rose-wood, are not as tall and have rather thick bark. In the first month of the dry season the leaves fall. New leaves sprout just before the rainy season begins.
The three types of climates in which deciduous trees grow are temperate, dry tropical, and moist tropical.
Temperate climates, such as in the northeastern United States, are moderate. Winters are cold and summers are warm with few extremely cold and hot days. The average temperature of a temperate deciduous forest is about 50°F (10°C), due to the rare extreme temperatures during the summer and winter.
There is plenty of moisture and few long, dry periods. A temperate forest usually requires at least 20 inches (51 centimeters) of precipitation (rain, snow, or sleet) each year, though most of these forests average between 30 to 60 inches (76 to 152 centimeters). The weather in a temperate climate can be very unpredictable. Precipitation usually occurs throughout the year, but much of it may fall as part of a severe storm system.
Temperate climates have four distinct seasons—spring, summer, fall, and winter. Warm weather begins in spring and temperatures gradually increase through the summer months. In the fall, the cooler weather takes over, and temperatures gradually drop to winter’s lows. During these cooler months the leaves of deciduous trees turn colors and then drop off. In winter, the trees are bare.
Dry tropical climate
In dry tropical climates, such as that in parts of India and Africa, the drop in precipitation is often accompanied by hotter temperatures. The length of the dry period and the level of heat help determine the type of trees that will grow there. In Tanzania, for example, severe dry periods may last up to seven months. Precipitation is often undependable, and when it does occur it may fall in large amounts. In India, for example, as much as 35 inches (89 centimeters) of rain may fall in a single 24-hour period. Leaves fall from the trees at the start of the dry period and grow again when the rains come.
Moist tropical climate
In tropical regions where moist climates occur, such as Myanmar and parts of India, temperatures remain high, but precipitation is more regular and predictable. In a rain forest, rain falls year-round, but in a moist tropical climate, dry periods occur. The dry periods are not as long or severe as in a dry tropical climate. As in dry climates, the trees shed their leaves when the dry period begins. New growth begins with the rains.
The geography of deciduous forests includes landforms, elevation, soil, and water resources.
Surviving the Ice Ages
During prehistoric times, before the great Ice Ages, North America and northern Europe were covered in deciduous trees such as walnut, hickory, sycamore, oak, maple, and chestnut. The climate was warmer than that of present times. As the ice advanced, the more delicate trees were forced to retreat to the south. In North America this was possible because the mountain ranges run north and south, which allowed the trees to spread along the valleys between them. In Europe, however, the mountains tend to run east and west, so the trees were trapped. For this reason, many European species did not survive, and the deciduous forests of Europe have fewer tree species than those of North America.
In the Northern Hemisphere, the landscape over which temperate deciduous forests grow includes mountains, valleys, rolling hills, and flat plateaus.
In the Southern Hemisphere, dry deciduous forests tend to occur near grasslands where the land is rolling or more nearly level. Moist deciduous forests are often found on mountainsides or rolling hills.
Elevation plays a major role in determining whether forest vegetation will survive because temperature can decrease rapidly with height. In addition, mountains tend to have a wetter climate than flat or low lands. On mountainsides, forests vary, mostly becoming smaller in overall size, and in individual tree size. The moist conditions appeal to lichens, mosses, and ferns, and these plants tend to thrive. Eventually, the elevation reaches a point where no tree can survive—this boundary is called the timberline or treeline. The timberline is contingent on temperature, not height, so it can occur in different places for different areas. For example, in Sierra Nevada, the timberline is located at 11,500 feet (3,500 meters), where as in the central Alps of Europe, the timberline is located at 6,800 feet (2,000 meters).
The soil in temperate deciduous forests tends to be deep and rich with a wide variety of nutrients because it receives a new blanket of leaves every autumn. The foliage of low-lying plants dies off and adds its own nutrient characteristics to the soil. During the winter, snow blankets the ground. Beneath its protective layer, bacteria, earthworms, and insects continue to break down the dead vegetation, creating dark humus. Humus is the spongy matter produced when the remains of plants and animals are broken down. It contains chemicals, like nitrogen, that are vital to plant growth, and it is able to absorb water. Oak leaves are difficult to break down so the soil beneath oak trees is not as rich.
In tropical climates, the soil differs from region to region. Soils in dry grasslands are sandy and dusty. Long, dry periods between the rainy seasons inhibits decomposition of dead plant matter and the release of nutrients, making the soil less rich. Moist tropical regions may have poor soil because topsoil is often washed away during heavy rains. Also, the shade is so dense that few smaller plants may grow there.
The presence of trees helps protect soil from erosion by holding it in place. Fallen trees are important in conserving and cycling nutrients and in reducing erosion. Trees also create windbreaks, which help prevent topsoil from being blown away.
In temperate regions, water resources include rivers, streams, springs, lakes, and ponds. In tropical regions, rivers, seasonal streams, and rain are often the primary sources of water.
Most forests contain a mixture of several types of trees and plants, and deciduous forests are no different. Stands (groups) of coniferous and non-coniferous evergreen trees may exist within their boundaries.
The trees and smaller plants in a forest grow to different heights, forming layers. The crowns of the tallest trees create a canopy, or roof. In the deciduous forests of eastern North America, the tallest trees are often oaks and hickories. Beneath their canopy grow shorter, shade-tolerant trees, such as maples. This shorter layer is called the understory. The next layer, only a few feet off the ground, is composed of small shrubs, such as junipers, and some flowering plants. The very lowest layer consists of small plants that live atop the soil.
In addition to trees, plant life within most deciduous forests includes bacteria; algae, fungi, lichens and green plants other than trees.
Algae, fungi, and lichens
Algae (AL-jee), fungi (FUN ji), and lichens (LY-kens) do not fit neatly into either the plant or animal category.
Most algae are single-celled organisms, although some are multi-cellular, and have the ability to make their own food. During a process called
A Nose for Truffles
In France, pigs, dogs, and even goats are trained to hunt truffles. A truffle is a type of edible fungus that grows under the soil in deciduous woodlands. Pigs are trained to recognize the smell of a truffle and sound an alarm when they find one. The truffles are then dug up and sold to people who consider them a delicacy.
photosynthesis (foh-toh-SIHN-thuh-sihs), they use energy from sunlight to change water and carbon dioxide (from the air) into the sugars and starches they require as food. Other algae may absorb nutrients from their surroundings. Although most algae are water plants, blue-green algae, which are actually bacteria, do appear in woodlands. They survive as spores (single cells that have the ability to grow into a new organism) during dry periods, and return to life as soon as it rains.
Fungi cannot make their own food by means of photosynthesis. Some, like molds and mushrooms, obtain nutrients from dead or decaying organic matter (material derived from living organisms). They assist in the decomposition of this matter, thereby releasing the nutrients needed by other plants. Other types of fungi are parasites, attaching themselves to other living things. Fungi reproduce by means of spores.
Fungi prefer moist, dim environments, and they thrive in shadowy forests of temperate regions. Common types of fungi include jack-o-lanterns, pear-shaped puffballs, fawn mushrooms, turkey tails, and destroying angels. Some, like chantarelles, grow directly on the soil, while others grow on the trunks of trees. Many, such as the fly agaric, are mushroomlike. Still others,
such as tree ears, resemble a porch roof as they protrude from tree trunks. Some mycorrhizae, surround the roots of certain trees, such as beeches and oaks, and help the roots absorb nutrients from the soil.
Lichens are actually combinations of algae and fungi that live in cooperation. The fungi surround the algae cells. The algae obtain food for themselves and the fungi by means of photosynthesis. It is not known if the fungi aid the algae organisms, although they appear to provide them with protection and moisture.
Lichens often appear on rocks and other woodland surfaces such as tree trunks and limbs. They are common in all types of forests and seem able to survive most climatic conditions. Lichens are a good indicator of air quality because many species will not grow in the presence of air pollution.
Green plants other than trees
Most green plants need several basic things to grow: sunlight, air, water, warmth, and nutrients. In deciduous woodlands, water and warmth are often abundant, at least seasonally. Light may be more scarce, but deciduous trees tend to be well-spaced, allowing sunlight to reach the forest floor. The remaining nutrients, primarily nitrogen, phosphorus, and potassium, are obtained from the soil and may not always be in large supply.
Woodlands are home to both annual and perennial plants. Annuals live only one year or one growing season. Perennials live at least two years or two growing seasons, often appearing to die when the climate becomes too cold or too dry, but returning to life when conditions improve.
Common deciduous forest green plants
In temperate climates, many species of small shrubs, mosses, ferns, herbs, and brambles thrive beneath the trees, along the edges of the forest, and in clearings. They include wildflowers such as lady’s slipper and columbines, and shrubs such as witch hazel, sumac, and spicebush. Shade-loving plants also grow beneath the trees. These include mayapple, jack-in-the-pulpit, poison ivy, and many species of ferns.
Trees have the ability to continue growing all their lives. This means that, in theory, they could live forever. When a tree dies, its death is usually caused by something in its environment, such as fire, wind, lightning, extremely dry periods, disease, insects, or being cut by humans. As a tree ages, it becomes more susceptible to disease and pests, and most trees die of several causes.
Green plants that grow close to the forest floor in temperate climates, such as the anemone, skunk cabbage, and trillium, appear in early spring when full sun can reach them. The primrose and the bluebell quickly bloom as the trees’ leafy canopy begins to form overhead. Later, when the trees are in full leaf, only the shade-loving plants, such as fern, moss, and ivy, will thrive. Growth continues throughout the summer then stops in autumn. Annuals die, leaving their seeds to carry through the winter. Although the foliage (above ground growth such as leaves and stems) of perennials die, their roots remain alive to send up shoots again the following spring.
In tropical climates, both dry and moist, the growing season begins just before the onset of the rainy season. It ends as the dry season begins. As in temperate climates, annuals die. Perennials usually have some method of storing water, such as a large taproot (a large center root that grows downward), that enables them to survive long periods without rain.
Most green plants reproduce by means of pollination (the transfer of pollen from the male reproductive flower part to the female). Pollen is carried by visiting animals, such as birds or insects, or by the wind, which blows it from one flower to another. As the growing season comes to an end, most green plants produce seeds. The seed’s hard outer covering protects it during cold winters or long dry seasons.
A few woodland plants, such as ferns, reproduce by means of rhizomes, long, rootlike stems that spread out below ground. These stems develop their own root systems and send up sprouts that develop into new plants. They also reproduce by spores that develop on the undersides of the leaf. When these spores mature, they are released from the plant and fall to settle on the soil where they begin to grow into a new fern plant.
In moist tropical regions, a layer of smaller evergreen trees often grows beneath the deciduous canopy. Both high- and low-climbing vines, and most smaller plants may in some cases be almost completely absent. In dry tropical regions, the lower layers may consist of thorny shrubs, cacti, grasses, and small palms.
Deciduous trees lose their leaves, which tend to be broad and flat, during cold or very dry periods. When temperatures are warm year-round and rainfall is constant, such as in a rain forest, these same trees may become evergreen and keep their leaves year-round. Trees are hardy perennials, but a number of factors can affect their life spans. Some of these are due to the environment, such as lack of sunlight or water, severe climate changes, disease, and fires. Many trees have short lives due to human consumption for land and timber.
The fact that most trees have a single strong stem, or trunk, gives them an advantage over smaller woody plants in that most of their growth is directed upward. Conifers often devote their energy to growing ever taller, while deciduous trees spread out their limbs and branches from their trunks to create a crown of leaves.
During autumn, trees in temperate regions lose the green color in their leaves because chlorophyll, a green substance in the leaves, breaks down. As a result, other colors present in the leaves are then visible, creating the brilliant hues of the autumn forest. This color change is brought on by shorter days, where hours of sunlight are decreased, and cooler temperatures.
Each year a deciduous tree grows, its trunk is thickened with a new layer, or ring, of vessels and other conduction cells that carry water and nutrients from the roots to the branches. When a tree is cut down, its age can be determined by how many of these rings are present. As a tree ages, the rings from the center outward become hardened to produce a sturdy core. In temperate climates, deciduous trees may grow from 2 to 5 feet (0.6 to 1.5 meters) in diameter and 60 to 100 feet (18 to 30 meters) in height during their life span.
Common deciduous trees
Typical deciduous trees in temperate regions include the ash, oak, maple, elm, poplar, birch, ginkgo, and magnolia. Tropical deciduous trees include the acacia, southern beech, baobab, teak, casuarina, cannonball, ebony, peepul, sycamore, and rosewood.
Oak Oaks are perhaps the best-known deciduous trees in temperate regions. Oaks are very adaptable to different environmental conditions. They are found in dry sandy plains to coastal swamps. All species of
A clone is an exact genetic copy of its “parent,” because it is grown from one of the parent’s cells. Cloning may someday become an important part of the forest industry. Cells from a superior adult tree could be cloned in a laboratory and the resulting seedlings planted on tree farms. As the trees grew, they would resemble the parent tree and be more uniform than a natural forest. Cloned trees have been grown from cells of redwood, Douglas fir, apple, citrus, and poplar trees.
oak have at least one thing in common—the acorn, or nut, that bears a scaly cap. The leaves of some oaks, such as the red oak, turn a brilliant color in autumn, while others are less colorful. Oaks are the dominant trees of central and western Europe. They are known for their excellent timber, which is valued for furniture and hard-wood floors.
Acacia Acacia (uh-KAY-shuh) trees are called thorn trees in Africa, wattles in Australia, and mimosas in North America and Europe. They are found in dry tropical climates as they can tolerate long, dry periods but they do not grow very tall. Acacias usually have an umbrella shape, yellow flowers, and sharp spines. Their seeds are used by both humans and animals for food.
Baobab Found in dry tropical regions, the baobab (BA-oh-bab) has a soft, spongy trunk and lower branches for storing large quantities of water. The trees lose their leaves during the dry seasons, which reduces water loss.
Baobabs do not grow very tall—about 16 to 82 feet (5 to 25 meters) in height. The trunk is often wide and may reach 23 feet (7 meters) in diameter. Giant baobabs are several thousand years old. Many animals
use the baobab for food and shelter, and pollination of its flowers is done by bats.
Teak The teak is native to India, Myanmar, and Thailand, where it prefers well-drained soils. It is a large tree with a spreading crown and small white flowers. Mature trees may reach 98 to 131 feet (30 to 40 meters) in height. Teak timber is known for being indestructible, and is commonly used in furniture, flooring, and other woodworking projects.
Moisture and temperature conditions are two important environmental factors affecting the growing season of deciduous trees. In temperate climates, the growing season takes place during the spring and summer and may last five to seven months. Some trees, such as beech and maple, produce their leaves earlier in the season, while oaks produce leaves later. In the autumn, cooler temperatures make it harder to absorb the water needed to maintain broad leaves. Broad leaves tend to lose a lot of water into the atmosphere. For these reasons and other factors including temperature and day length, the leaves die and fall off.
In tropical climates, growth slows or stops during hot, dry periods and the trees drop their leaves. Growth begins again when the rain comes. When dry periods are very long, trees in these areas may be stunted and develop very thick bark to protect against moisture loss.
Trees are divided into two groups according to how they bear their seeds. Gymnosperms produce seeds that are often collected together into cones. Most gymnosperms are conifers. In contrast, angiosperms have flowers and produce their seeds inside a fruit. Deciduous trees are usually angiosperms.
In temperate regions, many deciduous trees drop their seeds in the autumn. Some seeds may be contained in fruits in nut form, like acorns and beechnuts, or they may have papery wings, like the fruits of sycamores. In tropical regions, seeds fall just before or during the dry periods.
Trees can be threatened by natural dangers, such as forest fires, animals, and diseases, as well as by humans. Fires are more of a threat in dry climates, while animals and diseases are prevalent in all climates. For example, when deer populations get too large, they can destroy forests by eating wildflowers and tree seedlings. The caterpillar of the gypsy moth eats the leaves from a variety of tree species. If enough of these insects attack a stand of trees, all the leaves are eaten and the trees die. Dutch elm disease, a fungus transmitted by the elm bark beetle first seen in Holland in 1921, destroyed millions of elm trees in the United States in 1930. It was then
Chestnut Blight in the United States
Until 1940 the United States was home to the American chestnut tree, a graceful species with creamy white blossoms that often grew more than 100 feet (30 meters) tall. In 1904 foreign chestnut trees were imported into New York. These trees carried a fungus, called chestnut blight, which soon spread to American chestnuts. Over the next 40 years the fungus destroyed almost all the American chestnuts in the eastern half of the country.
Fortunately, the blight did not travel to the far west, and scattered, healthy American chestnuts are still found there. The roots of stricken chestnuts survived because the blight could not reach them underground. They continue to send up shoots but the shoots soon die because the fungus is still in the soil. Researchers are attempting to cross the American chestnut with other species resistant to the fungus in hopes of reestablishing the trees.
introduced to England in logs exported from the United States. It killed many elms there as well.
Pollution is a threat to birch, beech, ash, and sugar maple trees in the northeastern United States. Pollution appears to weaken the trees so that pests and diseases overtake them more easily. In western Europe, the beech is in decline.
From their roots to their tips, deciduous trees support a wide range of plant-eating animals and wild-life, while many other types of animals live among or beneath the trees. The animals can be classified as microorganisms, invertebrates, amphibians, reptiles, birds, and mammals.
A microorganism is an animal, such as a protozoan, that cannot be seen without the aid of a microscope. Every forest is host to millions of these tiny creatures. Microscopic roundworms, or nematodes, for example, live by the thousands in small areas of soil in deciduous forests and aid the process of decomposition.
Bacteria are always present in woodland soil where they help decompose dead plant and animal matter. In temperate climates, bacteria help create nutrient-rich humus. Fewer bacteria are at work in dry climates or in moist climates with long dry seasons.
Animals without backbones are called invertebrates. They include simple animals, such as worms, and more complex animals, such as wasps and snails. Certain groups of invertebrates must spend part of their lives in water. These types are not found in trees, but in ponds, lakes, and streams, or in pools of rainwater.
Some invertebrates, such as beetles, are well adapted to life in dry tropical forests. They have an external skeleton, a hard shell made from a substance called chitin (KY-tin). Chitin is like armor and is usually waterproof, protecting against the heat of the sun and preventing the animal from drying out. These same invertebrates do not survive as well in temperate forests because many adults die in the cold of winter. Their well-protected eggs or larvae may survive until the spring.
Common deciduous forest invertebrates
Invertebrates found in temperate forests include the tent caterpillar, the woolly bear caterpillar, the luna moth, the stag beetle, and the wolf spider. Other common invertebrates include the earthworm, the slug, the forest snail, and the acorn snail.
In tropical climates, many species of invertebrates, including the silkworm, inhabit moist forests. Dry climates have fewer insects; termites and grasshoppers are common, as are many species of caterpillars.
The Destructive Hitchhiker
In 1996, 2,400 trees in Brooklyn and Amityville, New York, were destroyed when the Asian long-horned beetle turned up in the United States. The 2-inch- (5-centimeter-) long insect lays its eggs just under the bark of maple, ash, elm, and horse chestnut trees. When the larvae hatch and seek food, they cut off vital nutrients to the trees starving them to death. It is believed that the beetle first made its way to this country in the wood packing materials of goods shipped from China.
In 1998 this black and white beetle was discovered in Chicago, Illinois. In an effort to stop the insect’s spread, 470 trees had to be cut down and burned. Burning is done during the winter months while the beetle is inactive and cannot escape. Hopefully all the infested trees were identified and destroyed, but there is no guarantee the beetles will not turn up somewhere else in the future.
Many invertebrates eat plants or decaying animal matter. The larvae of insects, such as caterpillars, are the primary leaf eaters in the deciduous forest. The tent caterpillar, the larvae form of a moth, spins a large, filmy, tent-like cocoon around a tree branch, which it soon picks clean. Weevils drill holes in acorns, which their larvae use for food, thus destroying the seed of the oak. Bees gather pollen and nectar (sweet liquid) from flowers, as do butterflies and moths, helping produce new plants through pollination. Arachnids (spiders), which are carnivores (meat eaters), prey on insects. Larger species may even eat small lizards, mice, and birds.
Most invertebrates have a four-part life cycle. The first stage of this cycle is spent as an egg. The egg’s shell is usually tough and resistant to long dry spells in tropical climates. After a rain and during a period of plant growth, the egg hatches. The second stage is the larva (such as a caterpillar). This may be divided into several stages between which there is a shedding of the animal’s outer skin. Larvae often spend their stage below ground where it is cooler and moister than on the surface. The pupal, or third stage, is spent hibernating within a casing (such as a cocoon). When the animal emerges from this casing, it is an adult.
Hide and Seek
Many animals use camouflage (KAH-mah-flahj; protective coloration) to disguise themselves from predators. Some predators camouflage themselves to lurk among tree leaves, waiting for their prey to pass by. The yellow color of the goldenrod spider, for example, enables it to hide in goldenrod flowers where it can sneak up on an insect sipping the flower’s nectar.
Amphibians are vertebrates (animals with backbones) that spend part, if not most, of their lives in water. Frogs, toads, and salamanders live in significant numbers in temperate and moist tropical deciduous forests. Frogs and toads can also be found in dry tropical forests if there is a dependable source of water.
Because amphibians breathe through their skin, and only moist skin can absorb oxygen, they must remain close to a water source. Mating, egg-laying, and young-adulthood all take place in ponds, lakes, or pools of rainwater. Offspring that survive and reach maturity leave the pools for dry land where they feed on both plants and insects. In dry tropical forests, amphibians must find shade during the day or risk dying in the heat of the sun.
Amphibians are cold-blooded animals, which means their bodies are about the same temperature as their environment. They need a warm environment in order to be active. As temperatures get cooler, they slow down and seek shelter. In temperate climates, amphibians hibernate (remain inactive) during winter months. In hot, dry climates, amphibians go through estivation, a similar inactive period. While the soil is still moist from the rain, they dig themselves a foot or more into the ground, where they remain until the rains return. Only their nostrils remain open to the surface.
Common deciduous forest amphibians
Amphibians common in temperate forests include spring peepers (tiny frogs that climb trees), spotted newts, Fowler’s toads, and marble salamanders. The African bullfrog is common to dry forests in Africa and the Pipid toad in South America. The flying frog is found in moist forests in India. It has a web of skin on both sides that begins at the wrist and attaches to the ankle. This skin acts as a parachute and enables the frogs to glide from one branch to another.
Adult amphibians are usually carnivorous, feeding on insects, slugs, and worms. Salamanders that live in water suck their prey into their mouths. Those that live on land have long, sticky tongues to capture food. Amphibian larvae are mostly herbivorous (plant eaters), feeding on vegetation. Frogs and toads are omnivores (both plant and meat eating) feeding on algae, plants, and insects such as mosquitoes.
Mating and egg-laying for amphibians must take place in water. Male sperm are deposited in the water, often right on top
of the female’s eggs. As the young develop into larvae and young adults, they have gills for breathing.
Reptiles that live in deciduous forests include many species of snakes, lizards, and turtles. The body temperature of a reptile changes with the temperature of the surrounding environment. Early in the day, they expose as much of their bodies as possible to the sun for warmth. As temperatures climb, they begin to seek shade. During hot, dry periods, they must find shade or a hole in which to wait for cooler weather. During chilly nights, they become sluggish. In temperate climates, snakes may hibernate in burrows during the long winter.
Common deciduous forest reptiles
Temperate forest reptiles in eastern North America include the five-lined skink, eastern box turtle, and garter snake. Reptiles found in dry tropical forests include the night adder, puff adder, Gabonan adder, and the agama lizard. Moist tropical forests are home to pythons and the calot lizard.
A lizard’s diet varies, depending upon the species. Some have long tongues with sticky tips and specialize in insects. Many are carnivores that eat small mammals and birds. The water they need is usually obtained from the food they eat.
All snakes are carnivores. One large meal (such as a rabbit, rat, or bird) can last them days or weeks. Constrictors squeeze their prey to death, while other snakes kill their prey with venom (poison) injected through the snake’s fangs.
Reptile eggs are leathery and tough. Offspring are seldom cared for by the parents. Some females remain with their eggs, but most bury them in a hole and leave. The young are left to hatch by themselves. Once free of the eggs, the babies dig themselves out of the hole and begin life on their own.
All forests have bird populations. Some species, such as the grosbeak, are migratory, which means they travel from one seasonal breeding place to another. During excessively cold or dry periods, most birds fly to more comfortable regions. Others, such as the blue jay, prefer to stay in the same area year-round.
Feathers protect birds not only from cold winters but from tropical heat. Air trapped between layers of feathers acts as insulation against both climates.
Common deciduous forest birds
In temperate forests, common birds include screech owls, great horned owls, hummingbirds, woodpeckers, nuthatches, woodthrushes, American redstarts, hawks, blue jays, cardinals, scarlet tanagers, chickadees, and turkey vultures.
Wrens, falcons, weaverbirds, and chats are found in dry tropical forests. In the moist deciduous forests of Australia, currawongs build nests of sticks in the eucalyptus trees. Thrush are common in India.
Jay Most species of jays are found in the Northern Hemisphere but they are also common in South America, Eurasia, and Africa. Their feathers may be drab or brightly colored, such as those of the North American blue jay. Many have crests and long tail feathers. They eat both plant matter and insects, and some species eat the eggs of other birds.
Jays are known for their bold, aggressive behavior and loud, harsh voices. Gangs of jays often harass other birds and even humans.
Falcon Found all over the world, falcons are birds of prey. They are characterized by long, pointed wings and the ability to fly very fast. Some species fly to a high altitude and then dive on their prey, killing it with the
powerful blow of their clenched talons. A peregrine falcon’s dive can reach more than 200 miles (322 kilometers) per hour during an attack.
The sport of falconry (training falcons to hunt other animals) originated in the East with the earliest records dating back to 700 BC in China. Falconry was also popular in Japan, Mongolia, Korea, and Russia.
Birds are found in greater variety and numbers where there is an ample supply of seeds, berries, and insects. Different birds seek food in different layers of the forest. Orioles and tanagers, for example, hunt for food high in the canopy. The white-breasted nuthatch hunts for insects along the trunks of the trees, and towhees dig around on the ground. Some birds that live year-round in temperate climates such as chickadees and blue jays may hide seeds in holes in trees where they can find them during the cold months. This hiding of seeds is called caching.
In dry tropical climates, such as that in most of Australia, birds adapt their breeding habits to periods of rainfall and breeding cycles may be far apart.
Birds are free to fly away from uncomfortable temperatures during the most of the year, but the breeding cycle dictates when they can travel. They must remain in the same spot from the time nest building begins until the fledgling birds can fly, a period of many weeks.
Parents usually sit on the nest to protect the eggs from heat or cold. During very hot weather, the parents may stand over the nest to give the eggs or the nestlings shade.
Mammals are vertebrates that have hair and bear live young. Only a few large mammals, such as bear and deer, live in temperate deciduous forests. Several small mammals, including mice, squirrels, woodchucks, and foxes, make their homes there. During the cold winters, many mammals burrow underground or find some other kind of shelter. Squirrels, for example, build nests high in the forest canopy. Some mammals, like bears, hibernate. In dry tropical climates, small mammals, such as rodents, may estivate (be very inactive) during the dry season.
Common deciduous forest mammals
Temperate forests are home to shrews, wood-mice, gray foxes, chipmunks, ground squirrels, badgers, black bears, silver-haired bats, raccoons, opossums, weasels, cottontail rabbits, gray squirrels, skunks, flying squirrels, and bobcats.
Dry deciduous forests support grazing animals, such as zebras and gazelles, which feed on the grasses that grow beneath the widely spaced trees. In the moist deciduous forests of Australia, red and gray kangaroos browse on leafy foliage. Wombats, opossums, and koalas live among the trees. Tigers are common in the moist forests of Asia, as are elephants and buffalo.
Raccoon Raccoons are medium-sized furry mammals with stout bodies, short legs, and long, bushy tails. They are perhaps best known for the black “mask” around their eyes and their proficiency as burglars. They prefer living in the woods where they hunt rodents, birds and bird eggs, berries, fruit, and other plant matter. They also love corn, melons and other foods of civilized life, which makes them expert raiders of suburban gardens and garbage cans.
Raccoons live in dens made in hollow trees. This is where they spend the daylight hours, and they go out to hunt at night. They sleep more during cold seasons, but they do not hibernate. Intelligent and curious animals, raccoons are hunted for their fur and meat.
Tiger The tiger is one of the largest and strongest carnivores. They can grow more than 9 feet (2.7 meters) from nose to tail and weigh as much as 500 pounds (227 kilograms). They are found in the Asia wild, where they prey on hoofed animals, such as wild deer and pigs, as well as fish, birds, leopards and, occasionally, bears. Although tigers are only successful in one or two attacks out of twenty, they sustain themselves by their ability to eat up to 80 pounds (36 kilograms) in one sitting. Only 5,000 to 7,000 specimens of tigers exist. Their population has decreased by 95 percent since the turn of the twentieth century, mostly due to habitat destruction.
Nature’s Johnny Appleseeds
Johnny Appleseed was the nickname of John Chapman (1774–1845), a man who traveled around North America planting apple trees. Some animals fulfill similar roles, although perhaps not on purpose. Squirrels and chipmunks, for example, prepare for the long winter by burying acorns and other nuts in the ground where they can dig them up later and eat them. They often forget where they buried them, and in the spring the nuts sprout and send up shoots. Thanks to the poor memories of squirrels and chipmunks, forests spread and grow.
Some mammals, such as mice, eat plants and insects. Others, like squirrels and hedgehogs, eat bird and reptile eggs and young. Many smaller mammals do not need to drink water as often because they obtain moisture from the food they eat.
The young of mammals develop inside the mother’s body. In this way they are protected from heat, cold, and predators. Mammals produce milk to feed their young. Those that live in dens must remain nearby until the young can survive on their own. In temperate forests, the young are usually born in the spring so they have many warm months ahead in which to grow strong.
In Asia, South America, and Africa, all the big cats, including tigers, leopards, and cheetahs, are endangered as humans encroach on their habitats. In some parts of the United States and Canada, the timber wolf remains threatened. In Australia, the koala and some species of kangaroos are threatened, as is the elephant in Africa and Asia. In some areas the animals are overhunted; in others their habitats are disappearing.
Humans are creatures of the forest. Until they learned to hunt, humans ate plant foods such as bark, nuts, and berries. The earliest records of
humankind show that people and the great forests evolved together. As humans learned to hunt animals for food and clothing, they sought out the forests, which had plenty of animal life.
Impact of the deciduous forest on human life
Forests have an important impact on the environment as a whole. From the earliest times, forests have offered food and shelter, a place to hide from predators, and many useful products.
Trees, soil, animals, and other plants all interact to create a balance in the environment from which humans benefit. This balance is maintained in what can be described as cycles.
The oxygen cycle Plants and animals take in oxygen from the air and use it for their life processes. When animals and humans breathe, the oxygen they inhale is converted to carbon dioxide, which they exhale. This oxygen must be replaced, or life could not continue. Trees help replace oxygen during photosynthesis, when they release oxygen into the atmosphere through their leaves.
The carbon cycle Carbon dioxide is also necessary to life, but too much is harmful. During photosynthesis, trees and other plants remove carbon dioxide from the air. By doing so, they help maintain the oxygen/carbon dioxide balance in the atmosphere.
When trees die, the carbon in their tissues is returned to the soil. If decaying trees become part of Earth’s crust, after millions of years, this carbon becomes oil and natural gas.
The water cycle Forests shade the snow, allowing it to remain in deep drifts. Root systems and fallen leaves help build an absorbent covering on the ground, allowing rain water and melting snow to soak into the soil and trickle down to feed underground streams and ground-water supplies.
Not only do forests help preserve water, but they also protect the land. Trees act as barriers, or walls, that help to reduce the strong forces of winds and rain. When forests are cut down, this barrier is removed and the topsoil is either blown away, or during heavy rains, the soil washes away. As a result, flooding is more common because there is no absorbent layer to soak up the rain. Since 1997, parts of India and Bangladesh have had severe flooding caused in part by the cutting of forests in the nearby Himalaya Mountains.
Trees take up water through their roots and use it for their own life processes. Extra moisture is released through their leaves back into the atmosphere, where it forms clouds and once again falls as rain or snow, continuing the water cycle.
The Nutrient cycle Trees get the mineral nutrients they need from the soil. Dissolved minerals are absorbed from the soil by the tree’s roots and are sent upward throughout the tree. These mineral nutrients are used by the tree much like humans take vitamins. When the tree dies, these nutrients, which are still contained within parts of the tree, decompose and are returned to the soil. These nutrients are then available for other plants and animals to use.
Since the earliest times, forests have been home to game animals, such as deer, which supply meat for hunters and their families. Forests also supply fruits and seeds, as well as vegetation for livestock, and honey made by bees. Cranberries, gooseberries, strawberries, raspberries, huckleberries, and currants all grow in temperate woodlands.
During prehistoric times, humans lived in the forest because it offered protection from the weather and dangerous animals. People of developed countries who continue to live in forested areas usually do so because they enjoy nature’s beauty. Some native tribes still live in forests, as their ancestors did many years ago.
Forests are important to the world economy. Many products used commercially are obtained from forests, such as wood, medicine, tannis, and dyes.
|WORLD TRADE IN TIMBER PRODUCTS (PARTIAL LIST)|
|Country||Exports: tons (metric tons)||Imports: tons (metric tons)|
|United States||12,948 (11,744)||16,778 (15,218)|
|Great Britain||---||5,484 (4,974)|
Healing Saps and Gums
Gums and saps from certain trees have important commercial uses. For example, the sap of the spiny acacia, called gum arabic, was first used by the ancient Egyptians to make inks. It has been used in medicines, adhesives, and is still used in making watercolor paints. These helpful liquids, which usually ooze from wounds in a tree, are produced only by trees that are unhealthy because of dry weather or poor soil and have been infected by microorganisms or fungi. The sap or gum may help the tree heal itself.
Trees produce one of two general types of wood: hardwood or softwood, based on the trees’ cell wall structure. Hardwoods are usually produced by deciduous trees, such as oaks and elms. Most coniferous trees, such as pines, produce softwoods. These names can be confusing because some softwood trees, such as the yew, produce woods that are harder than many hardwoods. Some hardwoods, such as balsa, are softer than most softwoods.
Wood is used for fuel, building structures, and manufacturing other products, such as furniture and paper. Wood used for general construction is usually softwood. In order to conserve trees and reduce costs, some manufacturers have created engineered wood, which is composed of particles of several types of wood mixed with strong glues and preservatives. Engineered woods are very strong and can be used for many construction needs.
Hardwood from deciduous trees is more expensive because the trees grow slowly. It is used primarily for fine furniture and paneling. Most of this hardwood comes from forests in Europe. In the United States, the major commercial hardwoods are sugar maple, red oak, black walnut, and beech.
In temperate regions, the soil beneath a deciduous forest is often fertile. For this reason, forestland has often been cleared for agricultural purposes. As the United States was settled, most of the original deciduous forest in the East was cut down to accommodate farms and large plantations. After the land was exhausted and farming became centralized in the plains of the Midwest, the forests gradually grew back. Oaks, maples, and hickories now flourish in the same regions that supported their ancestors 400 years ago.
Since the earliest times, plants have been used for their healing properties. The ancient Greeks, for example, used extracts from willow bark to relieve pain, as did certain tribes of Native Americans. During the nineteenth century, scientists discovered the bark’s pain-killing ingredient—salicylic acid. This ingredient is a component of the familiar pain-killing medicine, aspirin, made of acetylsalicylic acid.
Tannins and dyes
Tannins are chemical substances found in the bark, roots, seeds, and leaves of many plants. These tannins can be extracted by boiling or soaking plant material. The extract is then used to cure leather, making it soft and supple. Trees used for tannins include oaks, chestnuts, and quebracho.
Dyes used to color fabrics can be obtained from oak, alder, birch, walnut, brazilwood, and logwood. Natural dyes are no longer commonly used commercially, since less expensive dyes can be produced from chemicals.
Many people feel the need to escape to natural surroundings on occasion. The beauty and quiet of deciduous forests draw many visitors for hiking, horseback riding, skiing, fishing, hunting, bird watching, or just sitting and listening to nature.
The World’s Oldest Tree Species
The ginkgo (Ginkgo biloba), or maidenhair tree, is the only remaining survivor of a group of plants that thrived during the Permian period (260 million years ago). Essentially unchanged since prehistoric times, the ginkgo is a smooth-barked tree with fan-shaped leaves and few branches. Although it forms naked seeds, the ginkgo is deciduous; its leaves turn a golden color in fall and drop.
In China the ginkgo is sacred and is planted near temples. It is a popular ornamental plant in the temperate climates of Europe and North America. The seeds and leaves of the ginkgo are valued for their medicinal properties.
Impact of human life on the deciduous forest
Just as the forest has had an effect on human life, human life has had an effect on the forest. About 10,000 years ago, forests covered about half of Earth’s land surface. They now cover less than one-third. Nearly 2 billion tons (1.8 billion metric tons) of timber are cut from the world’s forests each year. Most of the losses in forest cover occur in developing nations where wood is used for fuel and trees are cleared for farming. The rest of the crop is used commercially.
Use of plants and animals
During the Middle Ages (500–1450) in Europe and the eighteenth and nineteenth centuries in America, it was thought that forests were indestructible. They seemed to go on forever. Eventually, the cutting of trees brought an end to many ancient forests. Only when they were left alone to regrow or were deliberately replanted, did the forests begin to recover.
In the United States, environmentalists are often in disagreement with logging companies over the cutting of old-growth forests. Trees are a renewable resource but old-growth trees may take more than 100 years to be replaced. Oftentimes, the logging companies replace the old trees with seedlings from other species that grow faster, and the original species are never
The Mighty Acorn
It is an old saying that “Mighty oaks from little acorns grow.” Acorns are appreciated for more than just turning themselves into oak trees. Many animals use them for food, and, at various times in history, humans have pounded them into a nutritious flour. In recent years a new use has been found: a cure for polluted rivers.
Acorns contain acornic acid, which binds with poisons from heavy metals, such as uranium, allowing these pollutants to be removed from rivers and streams. An estimated 2.2 pounds (4.8 kilograms) of acorns can clean up 3.5 tons (3.9 metric tons) of water.
replanted. The companies sometimes replace only certain species, destroying the forest’s diversity, along with plants and animals that depend on it.
Other threats to North American forests include mining operations that want to locate on public forest lands, and the cutting down of trees in order to develop land for homes and businesses.
Conservation laws in many states protect trees on public lands, while other laws protect forest creatures from being overhunted.
In tropical regions, forest land is being lost as populations grow and want the land for farms. Slash and burn agriculture is practiced when trees are cut and burned. The land is then used between one and five years for farming. When the land, which is usually poor, no longer supports crops, it is abandoned and another forest plot is cut down elsewhere. As a result, many animals and plants lose their habitats.
Quality of the environment
Destruction of the forests does not just mean loss of their beauty and the products they provide. Soil quality declines. Some soil is washed away by rain, and the loss of plant life means the soil will not be built back up again.
Water quality and supply also suffers. With the loss of trees, rain does not seep into the soil and underground water reserves are not replaced. Soil that is washed away often ends up in streams and rivers. If the quantity of soil is large enough, fish may die.
Air quality is reduced when forests are destroyed. Not only do trees put oxygen back into the air, but soot and dust collect on their leaves. When it rains, the trapped soot and dust are washed to the ground where they enter the soil. In this way, trees help keep the air clean. When trees are cut down, the dust and soot remain, contributing to air pollution.
Carbon dioxide and other undesirable gases have built up in the atmosphere with the popularity of the automobile. Most scientists believe these gases are helping to raise the temperature of Earth’s climate by forming an invisible layer in the atmosphere. This layer traps heat instead of letting it escape into the upper atmosphere. This is called the “greenhouse effect.” Cutting down forests may be helping cause this global warming because they can no longer remove carbon dioxide from the air. If Earth
|North America and Europe||Central and South America||Africa||Asia||Australia|
|Alder||Aromata||African oak||Aralia||Black bean|
|Ash||Balsa||African walnut||Bow wood||Cedar|
|Basswood||Bois gris||Comphorwood||Boxwood||Coconut palm|
|Dogwood||Lignum vitae||Gum||Tea tree|
|Plane||Tree of Heaven|
continues to grow warmer, many species of plants and animals could become extinct.
Air pollution is contributing to forest loss as well. Some forests take on an off-color, or sickly, appearance in polluted environments. Air pollution causes acid rain, which damages some types of trees. Acid rain occurs when certain compounds in polluted air mix with water vapor and fall to Earth in rain. When acid rain is absorbed into the soil, it can destroy nutrients and make the soil too acidic to support some species of trees. Forests in northern Europe, southern Canada, and the eastern United States have been damaged by acid rain.
Off-road vehicles, such as motorbikes and four-wheelers, tear up forest undergrowth, kill flowers, scare away animals, and destroy the peace of the forest.
The U.S. National Forest Service was established in 1905 to protect forest resources. More than 193 million acres (78 million hectares) of land are now publicly owned. Most of this acreage is west of the Mississippi. Forests in the eastern half of the United States are managed by state programs. These forests may consist of land that can be used for logging and other commercial purposes; however, certain portions are kept for recreation and conservation.
Other nations, including Great Britain, Japan, China, and India, have established programs to conserve and replant forests.
By 1950, native peoples in industrialized parts of the world had abandoned most of their tribal lands and customs. Many went to live in cities but some still live a traditional lifestyle. The Birhor of central India are one example. They live in the forests as nomadic hunter-gatherers and supplement their diet with rice that they trade for with forest products such as bark fiber rope.
Algonquin and Iroquois Tribes
Until the European settlers forced them off their ancestral lands, many Native American tribes lived in the deciduous woodlands of the northeastern United States. They included tribes who spoke the Iroquois language—the Cayuga, Erie, Huron, Mohawk, Oneida, Onondaga, Seneca, Tuscarora, and Neutral; and those who spoke Algonquin—the Delaware, Fox, Illinois, Kickapoo, Mohican, Massachuset, Menominee, Miami, Mohegan, Ottawa, Pequot, Sauk, Shawnee, Shinnecock, and Wampanoag.
Long winters in those regions limited farming, so most foods were collected from the wild. These included fish, game, maple syrup, and wild rice.
Nearly all native groups who survived contact with European settlers were forced to move to reservations in Oklahoma during the early nineteenth century.
The Ainu are native peoples who live on Hokkaido, the northernmost island of Japan, and on the Russian island of Sakhalin in the North Pacific. Originally hunters and gatherers, the men used bow and arrow to hunt bear, deer, fox, otter, and other animals during the winter; in summer they fished. The women gathered roots, berries, mushrooms, and nuts and also did some farming. The men were skilled woodcarvers, and the women wove fabrics and did embroidery. Their chief musical instruments were the drum and flute.
At one time, the Ainu lived throughout the Japanese islands, but gradually, as the Japanese population has moved in and expanded, the Ainu have been pushed to their present territory. As of the last census in 1984, the population was only 24,381 people.
The transfer of energy from organism to organism forms a series called a food chain. All the possible feeding relationships that exist in a biome make up its food web. In the deciduous forest, as elsewhere, the food web consists of producers, consumers, and decomposers. An analysis of the food web shows how energy is transferred within the biome.
Green plants are the primary producers in the forest. They produce organic materials from inorganic chemicals and outside sources of energy, primarily the sun. Trees and other plants turn energy into plant food.
Animals are consumers. Plant-eating animals, such as grasshoppers and mice, are primary consumers in the forest food web. Secondary consumers eat the plant-eaters. Tertiary consumers are predators, like owls, foxes, and tigers. They are carnivores. Humans fall into this category, but they are omnivores, which means they eat both plants and animals.
Decomposers feed on dead organic matter, and include fungi and animals like the turkey vulture. In moist environments, bacteria also help in decomposition. When fallen leaves from deciduous trees carpet the ground forming a thick layer, bacteria feed on the leaves and help decompose them into humus.
Deciduous forests of Medieval Europe
About 5,000 years ago, birch trees dominated the forests of the Northern Hemisphere. As the climate gradually became warmer other trees started to take over. By Medieval times (500–1450), many hardwood trees, such as beeches and long-lived oaks, ranged over much of central and western Europe north of the Alps and the Pyrenees Mountains, and eastward across Russia to the Ural Mountains. Oaks and beeches usually formed the canopy, with maples and birches in the secondary layer, and dogwoods, hawthorns, and hollies closer to the ground.
Forests of Medieval Europe
Location: Northern and western Europe
The forests were home to falcons, hawks, herons, owls, deer, wolves, boars, otters, squirrels, foxes, badgers, and other wild animals. Many of these were hunted; some for food and others to protect crops and domesticated animals.
The people who lived there depended on forests as a source of timber for building livestock houses, vines and leaves for feeding, and game animals for hunting. Bees, prized for their honey, were often kept within the forest, and the fruits and nuts of many trees, such as the hazel, were used as food. Pigs were kept in the forest where they could feed on acorns. Valued for these nuts, oaks were allowed to grow old. Wood was prized as fuel, not only as logs but as charcoal, which is created when wood is partially burned. Charcoal produces a very hot fire and was used in beer brewing and forging iron. Wood ash, a by-product of burning wood, was needed for making glass and soap. Wood was used to build boats, carts, furniture, and even shoes.
Open land was used for farming but as populations grew, more and more forests were cut down and used for planting crops. By the eleventh century, the heavy plow came into use. It worked the soil more efficiently than previous methods and increased the amount of land that could be used for agriculture.
Deciduous forests of Japan
Japan is a series of islands, and deciduous forests cover at least half of the largest island, Honshu, and the lower-lying parts of southern Hokkaido.
Deciduous forests of Japan
Location: Northern Japan
Beeches are the dominant trees, but many other species are mixed in, including oaks, chestnuts, maples, and limes. Oaks and chestnuts are cultivated on privately owned tree plantations. Much of the land in Japan is intensely cultivated because it is a small country in terms of available land. This has led to the production of miniature trees that can be planted in small gardens.
The climate of Japan’s deciduous forests is temperate but cool. Rain is plentiful, as is snow in winter. The stately beeches, which have bright green leaves in summer, turn a rich gold-brown in autumn.
Few trees are planted in Japan for timber. Most commercially grown trees, such as the beautiful Japanese maple and the flowering cherry, are sold for ornamental purposes.
Deciduous forests of China
China is the third largest country in the world based on acreage, and its forested land stretches over many hundreds of thousands of square miles. In the north, the climate is cool temperate, while in the south the climate is warm temperate. Oak, ash, birch, and poplar forests predominate in the northeast. No single species predominates in the southeast, and even the canopy shows a mixture of trees, including oak, maple, poplar, boxwood, and sweetgum.
Deciduous Forests of China
Location: Eastern China
The world’s first artificial forest was located in China, and is currently 115 million acres large (46 million hectares). It accounts for 26 percent of the world’s artificial forests and covers 16.5 percent of China’s land mass—more than double the 8.6 percent China had in 1950.
Deciduous forests of North America
Deciduous forests are found in North America in portions of southern Canada, New England, the upper Midwest, the Appalachian region, along the Mississippi, and in the southeastern states.
Deciduous Forests of North America
Location: Southern Canada and eastern United States
When European settlers arrived in America in the 1600s, these forests were thick with oak, beech, and chestnut trees. Many trees were at least 100 feet (31 meters) tall and shaded a wide variety of other plants. Wild turkeys, passenger pigeons, moose, cougars, bison, beavers, otters, bears, and wolves were present. By 1970 most of the deciduous forests had been cut down, sacrificed to the building of houses and the need for farmland. Only in remote areas where the land was too steep to allow easy access did the original forest survive.
In some areas, deciduous forests are recovering. New England, for example, has more forest now than there was 100 years ago. Deciduous trees, such as sugar maple, birch, beech, and hemlock, mingle with coniferous forests. From Minnesota and Michigan eastward toward New England, the land is now being reclaimed by oak, beech, maple, aspen, and other species. In the southern and southeastern United States, the land was once covered primarily by deciduous trees, such as oaks, which were cut for timber and to clear the land for farms. Coniferous trees now predominate in some areas. If the land remains undisturbed, deciduous trees will once again take over.
Deciduous forests of Australia
Only about 15 percent of the total area of Australia has enough rainfall to support forests. Its central region is primarily desert mixed with grassland, and its forests grow in bands on the outer fringes of the continent. Although most of these trees are evergreen, moist deciduous forests can be found along the north and northeast coasts. Along the southern edge of the continent are open woodlands and dry tropical forest mixed with grasslands.
Deciduous forests of Australia
Location: Along the coastlines of the continent
Classification: Moist tropical and dry tropical
In the more humid upland and coastal areas of southwestern and eastern Australia, eucalyptus, angophora, and sheoaks predominate, mixed with beeches in some areas and shrubs having leathery leaves. In the south, acacia, or wattle, trees are common.
Woodland animals are varied and include many poisonous snakes. One interesting species, the carpet snake, is not poisonous but suffocates its victims by wrapping itself around them. A climber, the carpet snake is often turned loose in barns by farmers who want it to catch rats and mice.
Forest birds include budgerigars, currawongs, honey-eaters, and laughing kookaburras.
Mammals are predominantly marsupials, such as wombats and kangaroos, that carry their young in a pouch. Kangaroos range through the open woodlands of eastern Australia.
The native peoples of Australia are the Aborigines, who live in dry regions.
Deciduous forests of Central India
Central India, in the general area between the cities of Delhi and Nagpur, is a dry tropical region with dry and mixed deciduous forests. Trees found here include teak, mango, mohwa, jamun, gardenia, sal, and palm. Much of the area is grassland, and bamboo is common.
Deciduous forests of Central India
Location: Central India between Delhi and Nagpur
Classification: Dry tropical
The region supports many parks and nature preserves, including Kanha Tiger Reserve and Taroba and Shivpuri National Parks.
Animals in this region include jays, peacocks, demoiselle cranes, wild boar, sambar and chital deer, gazelles, jackals, leopards, and tigers.
Forests account for only about 10 percent of India’s land area, and forests are not accessible for commercial development. The government is attempting to increase the forested area by outlining three key goals—reduce soil erosion, supply wood product industries, and supply the needs of the rural population.
Deciduous forests of Southern India
Several regions at the southern tip of India support moist tropical deciduous forest and mixed forests with many evergreens. Trees include teak, ebony, and bejal. Except for areas devoted to the cultivation of teak, undergrowth tends to be thick. Open areas are covered by grasses and bamboo.
Deciduous forests of Southern India
Location: The tip of India, south of Bangalore
Classification: Moist tropical
Several reserves and national parks are located here, including the Mudumalai Sanctuary, the Nagarhole Sanctuary, and the Bandipur Tiger Reserve.
The animal population is rich and varied. Termite nests can be seen along the roadways. Pythons, cobras, and monitor lizards are common. Birds include peacocks, parrots, pigeons, hornbills, and drongos. Giant squirrels, elephants, gaurs, lipped bears, leopards, and tigers also make their homes in the forest.
Deciduous forests of Tanzania and Kenya
In Tanzania, the forest is called miombo. As of 2000, 41 percent of the Tanzanian land mass was covered in forests. Their trees are short with flat tops. During the dry season, which may last as long as seven months, the trees shed their leaves. Grasses and other plants die off, and the forest looks brown and scorched. When new leaves begin to appear, they signal the start of the rains, which give new life to the region.
Deciduous forests of Tanzania and Kenya
Location: Eastern Africa
Classification: Dry tropical
Tree seedlings often develop large tap roots used to store water. During this time there is little development of the tree above the ground. Trees may take as long as seven years to grow more than 1 foot (30 centimeters) in height.
In Kenya, acacia woodlands are common, although baobab is predominant. Seasonal droughts cause vegetation to die. Many trees store water in tap roots or, like the baobab, in their trunks. A single baobab trunk can contain up to 25,000 gallons (94,625 liters) of water.
Common animals include the buffalo, elephant, leopard, lion, rhinoceros and wildebeest. Lions are the largest predator.
Allaby, Michael. Biomes of the Earth: Temperate Forests. New York: Chelsea House, 2006.
Allaby, Michael. Temperate Forests. New York: Facts on File, 2007.
Braun, E. Lucy. Deciduous Forests of Eastern North America. Caldwell, NJ: Blackburn Press, 2001.
Hurtig, Jennifer. Deciduous Forests. New York: Weigl Publishers, 2006.
Jacke, Dave. Edible Forest Gardens. White River Junction, VT: Chelsea Green Publishing Co., 2005.
Johansson, Philip. The Temperate Forest: A Web of Life. Berkely Heights, NJ: Enslow Publishers, 2004.
Yahner, Richard H. Eastern Deciduous Forest, Second Edition: Ecology and Wildlife Conservation. Minneapolis, MN: University of Minnesota Press, 2000.
Bright, Chris, and Ashley Mattoon. “The Restoration of a Hotspot Begins.” in World Watch 14.6 Nov-Dec 2001: p. 8–9.
Kessler, Rebecca. “Spring Back.” in Natural History 115.9 November 2006: p 18.
Shefrin, Russell. “An Optimistic Look at Falling Leaves.” in New York State Conservationist 62.2 October 2007: p32.
Environmental Defense Fund, 257 Park Ave. South, New York, NY 10010, Phone: 212-505-2100; Fax: 212-505-2375, Internet: http://www.edf.org
Friends of the Earth, 1717 Massachusetts Ave. NW, 300, Washington, DC 20036, Phone: 877-843-8687; Fax: 202-783-0444, Internet: http://www.foe.org
Global ReLeaf, American Forests, PO Box 2000, Washington, DC 20013, Phone: 202-737-1944, Internet: http://www.amfor.org
Greenpeace USA, 702 H Street NW, Washington, DC 20001, Phone: 202-462-1177, Internet: http://www.greenpeace.org
The Wilderness Society, 1615 M St. NW, Washington, DC 20036, Phone: 800-the-wild, Internet: http://www.wilderness.org
National Geographic Magazine. http://www.nationalgeographic.com (accessed August 22, 2007).
National Park Service. http://www.nps.gov (accessed August 22, 2007).
Nature Conservancy. http://www.tnc.org (accessed August 22, 2007).
Scientific American Magazine. http://www.sciam.com (accessed August 22, 2007).
USDA Forest Service. http://www.fs.fed.us (accessed August 22, 2007).
The World Conservation Union. http://www.iucn.org (accessed August 22, 2007).