Globio

Four-Season Forests

Temperate forests grow between the tropics and the polar regions in both the Northern and Southern Hemispheres. They have four distinct seasons with a well-defined winter. Temperate forests have a moderate climate. They are home to many plant and animal species. Much of the food humans eat is grown in areas where temperate forests have been cleared and farms now exist. If you don’t live in the tropics, chances are a temperate forest once was growing where you are right now. Temperate forests are also where many of our favorite foods first came from. Walnuts, apples, mushrooms, and maple sugar are all foods of the temperate forest.

The soil in temperate forests is rich in nutrients. Temperate forests are often cleared to make way for farms, houses, and golf courses.

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Trees of Temperate Forests

Temperate forests include a mix of trees that belong to three main groups.

Deciduous trees lose their leaves when the days grow shorter and the weather turns cold. The leaves grow back when the weather warms in the spring and the days grow longer. Trees like maples, oaks, chestnuts, beeches, and elms are examples of deciduous trees.

Coniferous trees have seeds that develop in cones. These trees usually have needles for leaves. The trees lose the needles gradually so that the tree is never bare. Coniferous trees are also called evergreens, because they are green all the time. Pines, firs, and cedars are examples of coniferous trees.

Broad-leaved evergreens grow in temperate forests in warm parts of the world like New Zealand, Australia, southwest South America, and the Mediterranean. These trees have flat, leathery leaves. These trees do not lose their leaves in the winter. The leaves are waxy, which helps keep them from losing too much water in winter when the air is dry. Olive, holly, tea, and eucalyptus trees are all broad–leaved evergreens.

Animals like koalas and wallabies are temperate forest species that live in the warmer, broad-leaved evergreen forests of Australia.

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In Temperate Forests, Litter Is a Good Thing

Fallen leaves create leaf litter. Leaf litter is one of the most important parts of the temperate forest. This is where the forest recycles most of its nutrients. Inside and beneath this leaf litter, thousands of small animals live, including many invertebrates like beetles, millipedes, centipedes, and ants. Unseen microscopic creatures such as fungi and bacteria live there, too. All these organisms help break the leaf litter into nutrients other plants and animals can use.

A Different Look Each Season

Seasons change the look of temperate forests every few months. The four seasons are winter, spring, summer, and fall.

Winter - Forests may look rather lifeless during this time, especially if the forest is made up mainly of deciduous trees. Most wildlife hides from the cold or flies far away to warmer places. Many temperate forests are blanketed in snow for much of the winter.

Spring – Days begin to lengthen and get warmer. Wildlife slowly returns and new leaf and flower buds appear on deciduous trees. Insects hatch and become food for many returning birds and awakening rodents and reptiles.

Summer – The forest is green and food is plentiful. Woodland animals have babies. The forest is awake and busy during the day and night.

Fall – As daylight shortens and temperatures fall, deciduous trees reduce the amount of green chlorophyll in their leaves. The leaves turn orange, yellow, red, and brown. Falling leaves create thick leaf litter on the forest floor that will be recycled into the soil. Animals store nuts and other food resources for the winter when there will be very little food.

Temperate forests have four distinct seasons: winter, spring, summer, and fall. Each season has different temperatures and weather patterns.

©G.Ellis/GLOBIO.org/©Flow Simulation Ltd.

Precipitation

Each forest receives a different amount of precipitation in the form of rain and snow. Temperate forests consisting mainly of broad-leaved evergreens receive the least. Most forests get their precipitation in winter and spring. Annual precipitation in temperate forests ranges from 75-150 cm a year.

A Temperate Forest from Top to Bottom

Temperate forests can be divided into three layers: the canopy, understory, and forest floor.

Open up the forest below to discover more.

Temperate Forest Creatures

Many of the animal species we know and recognize live in temperate forests. In Australia, koalas, possums, wallabies, wombats, kookaburras, and many small marsupials depend on the forest. In Europe, boars, badgers, squirrels, and songbirds live in temperate forests. In Canada and the United States, deer, bears, mountain lions, bobcats, rabbits, woodpeckers, and many smaller birds make the temperate forest their home. In China, endangered species such as giant pandas and red pandas survive in the temperate forest.

Wildlife in temperate forests is not always easy to see. Many species have markings or coloring that camouflages them. Others are nocturnal, that is, they are most active at night. Owls, bats, possums, and many wild cats are nocturnal.

A Food Supply That Comes and Goes

Food supply affects when and where most wildlife is found. In the spring and summer, food is plentiful, and the weather is mild. Most animals have babies during this time of the year. In winter, plants go dormant, insects disappear, and there are no fruits or flowers. Very little food is available during the winter months. For this reason, most wildlife either sleeps in a den or nest or migrates to a warmer place.

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Valuable Timber and Rich Soil

Temperate forests are important for people, too. Many trees that people use for timber to make houses, ships, and furniture grow in temperate forests. Trees from temperate forests are also used to make paper and other products. The land beneath these forests is often very rich and good for farming. People have cut many temperate forests to make space for farms.

Nature’s Cleaning Service

Temperate forests provide people with many more resources than just wood and farmland. Clean air and clean water are direct benefits of a healthy forest. In countries like Australia, protection of temperate forests is critical to maintaining clean water. In areas where the forest has been clear cut, the soil loses it nutrients and may wash away. Over time, few plants can grow anymore and the land looks like a desert.

Acid Rain

In the last 30 years, scientists have discovered that air pollution from factories, coal-burning power plants, cars, and other sources mixes with rain to make acid rain. Over time, acid rain kills trees and other plants.

Conservation of areas of temperate forest can protect many species that call the forest home, like this endangered northern spotted owl.

©G.Ellis/GLOBIO.org

An Uncertain Future

Conservation of temperate forests is important but difficult to carry out. People often demand that their needs come before those of wildlife and the long-term health of the forests. This approach could mean that in the future the only large areas of temperate forest will be those protected in national parks and sanctuaries.