Deciduous and Evergreen Trees

Two ways to be a tree

Take a walk in a park in winter. You will notice something. Some trees stand bare, with no leaves at all, just dark branches against the sky. Other trees are still green and leafy, even in the cold and snow. These are the two great families of trees: deciduous and evergreen.

Deciduous trees: the leaf-droppers

Deciduous trees lose all their leaves once a year, usually in autumn. The word "deciduous" even comes from a Latin word meaning "to fall off".

Each autumn their leaves change colour and drop, and the tree spends winter completely bare. Then, when spring returns, it grows a whole new set of fresh green leaves. Common deciduous trees include:

• Oak
• Maple
• Birch
• Apple and other fruit trees
• Beech

Why drop perfectly good leaves? Winter is cold and the ground may freeze, so the tree cannot easily drink water. Broad, thin leaves would lose water and could be damaged by frost. By going bare, the tree saves water and energy and rests safely until spring. You can read more about this in Why Leaves Change Colour in Autumn.

Evergreen trees: green all year

Evergreen trees keep their leaves all year round. They are never fully bare. They do drop old leaves, but only a few at a time, so we never notice — there are always plenty of green ones left.

Many evergreens are conifers, which means they make seeds inside cones. Instead of broad flat leaves, conifers usually have thin, pointed needles. Common evergreens include:

• Pine
• Fir
• Spruce
• Holly (which has broad leaves, not needles)

Why needles are clever

Evergreen needles are perfectly built for surviving cold, windy places.

• They are thin and narrow, so they have very little surface to lose water from.
• They have a tough, waxy coat that locks water in and keeps frost out.
• Their shape lets snow slide off instead of piling up and snapping branches — that is why a fir tree has its classic triangle shape.

Because they keep their leaves, evergreens can start making food the moment there is a little sunshine, even in early spring, without waiting to grow new leaves first. This food-making is called photosynthesis.

Which is better?

Neither! They are just two different solutions to the same problem: how to survive winter. Deciduous trees shut down and rest; evergreens tough it out with hardy needles. Both have lived on Earth for millions of years. In cold northern forests, evergreens often win. In milder places with warm summers, deciduous trees do very well. To see how all trees grow from a seed, read How Trees Grow.

Activity: become a tree spotter

You can learn to tell the two kinds apart.

1. In winter, look around your street, park or schoolyard. Make two lists: "bare trees" (deciduous) and "still green" (evergreen).
2. Look at the leaves you find. Are they broad and flat, or thin needles? Needles almost always mean an evergreen conifer.
3. Hunt for cones under the green trees — a sure sign of a conifer.
4. Pick one deciduous tree and one evergreen near your home. Draw them now, then draw them again in spring. The evergreen will look almost the same. The deciduous tree will be covered in brand-new leaves!