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WHY DO THESE TREES SHED THEIR LEAVES?

When trees shed their leaves they stop

growing. This helps them conserve energy

during winter, when there is not enough

sunlight to make food. Shedding leaves

also helps trees conserve water as it

stops water evaporating from them.

DECIDUOUS TREES

Trees that lose their leaves in the autumn are

called deciduous. They grow in temperate

places that have warm summers and

cool or cold winters.

CANOPY

The upper part of the trees in any forest or

woodland is called the canopy. It is made

up of their branches, twigs, and leaves.

Tropical rainforest trees form a dense

canopy that is home to many animals.

WHY DO DECIDUOUS

LEAVES CHANGE COLOUR?

In summer, these leaves are

packed with the green pigment

(colouring) chlorophyll, which

captures sunlight energy. In

autumn, chlorophyll breaks

down and is reabsorbed by the

tree, revealing previously hidden

pigments, such as reds, yellows,

and oranges.

WHY ARE RAINFOREST TREES SO TALL?

In hot, steamy rainforests, the tightly packed trees

grow rapidly and to great heights. This is because

they are all competing for sunlight. The taller the

tree, the more light its leaves will receive. Some trees

can reach heights of up to 60 m (197 ft).

WHAT IS AN EPIPHYTE?

An epiphyte is a plant that grows on a larger one

without harming it. Many epiphytes live high up in

the rainforest canopy, firmly anchored by their roots

to tree trunks and branches. In the canopy, epiphytes

receive much more light than the plants on the forest

floor, and more rain water.

1 DECIDUOUS TREE IN SUMMER

This lime tree is bathed in

summer sun. The tree uses its

mass of green leaves to trap

sunlight energy to make food.

DECIDUOUS TREE IN AUTUMN 1

In autumn, temperatures are

lower and there is less daylight.

The lime tree’s leaves turn orange

or brown and start to fall.

4 REACH FOR THE SUN

This is the view that someone standing on the rainforest floor would

see when looking upwards. A palm tree in the shrub layer uses its large

leaves to trap sparse sunlight filtering down through the canopy above.

Floor

CHANGING LEAF COLOUR 3

The leaves of deciduous

trees turn from green

to orange, yellow, or

red with the coming

of autumn, or in very

dry weather conditions.

Shrub

layer

Canopy

Understorey

Emergent

layer

Evergreen,

broad-leaved tree

Canopy

Rainforests are made up of distinct layers. In the emergent layer, the

very tallest trees stick out from the canopy. Beneath the canopy is

an understorey of smaller trees and a shrub layer of big-leaved

plants that can live in low-light conditions. Below this is the dark

forest floor, where there are fewer, smaller plants.

LAYERS OF A RAINFOREST

PERSIAN IRONWOOD LEAVES

Palm tree has
broad, branched
leaves

Sunlight filters through

to reach the forest floor

FIND OUT MORE. Flowering Plants 92–93 • Non-Flowering Plants 90–91 • Plants 88–89

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