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Adaptations: Deciduous forests

Adaptations: Deciduous forests

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What happens to the leaves of deciduous trees in the spring?

Adaptations: Deciduous forests

This is a forest on the east coast of Canada. Right now it is spring, and the forest is green and full of life. But, if we come back to this same forest later in the year, it will look very different Similar forests are found in temperate regions around the world that experience four distinct seasons - spring, summer, autumn, and winter - and significant temperature changes throughout the year. The plants in these forests must be able to adapt to these changing conditions. The most important adaptation has to do with leaves.

Most trees in this forest have large, thin, lightweight leaves. These leaves are well suited for capturing a lot of sunlight. The trees then use this sunlight to make nutrients through photosynthesis. But when the weather gets cooler, these large leaves become troublesome. They allow a lot of water to evaporate from the tree.

Because the ground is frozen in winter, the trees cannot regain this water easily. Additionally, the broad leaves provide a large area that wind can act on and snow can gather on. This can put strain on the tree, a serious concern in winter storms and gales. The trees in this forest have adapted: they drop their leaves in the autumn and grow new ones in the spring. They are deciduous trees and this is a deciduous forest.

Oaks, beeches, birches, chestnuts, aspens, elms, and maples are some examples of deciduous trees. The deciduous forest is made up of layers of plants. The tallest trees make up the forest canopy which can be 30 metres or more above the ground. Beneath the canopy are smaller and younger trees. They form the understory.

These understory trees have adapted to being in the shade of the canopy: they tend to have larger leaves that help them capture the little light available. Below the understory is a shrub layer, characterised by vegetation that grows relatively close to the ground. Bushes and brambles grow where enough light passes through the canopy. Then, carpeting the forest floor is a herb layer made up of wildflowers, grasses, and ferns. Plants in the herb layer grow quickly in the spring.

This allows them to absorb as much sunlight as possible before the other layers block the full strength of the sun with their large leaves. Animals in deciduous forests have also adapted to the changing seasons. Larger mammals such as bears and groundhogs spend the summer eating as much as possible. The weight they gain during this time allows them to enter a long period of inactivity during the winter. This is called hibernation.

When the weather is cold and food is scarce, hibernating allows these animals to survive until spring. Food storage is another adaptation some of the animals have. Chipmunks and squirrels, for example, gather nuts and seeds, storing them in hollow logs or holes in the ground in the summer to use as food in the winter. Birds deal with the cold winter in another way. When the temperature turns colder in the autumn, most birds leave the deciduous forest for warmer regions where food is easier to find.

They migrate, often thousands of kilometres. In the spring, the birds return to the deciduous forest to build their nests. Hibernation… Food storage… And migration are three adaptations that many deciduous forest animals have. When it comes to plants: Deciduous trees shed their leaves in the autumn… Understory plants are shade-tolerant… And herbs sprout early to maximise photosynthesis.