Category Chemistry

Most of the wood we use is specially grown in large forests. These forests are carefully planned to help the trees grow well. The kinds of trees planted are the ones that will grow best in the forest’s soil and weather.

These baby trees are growing in a tree nursery.

Conifer tree seeds are collected from pine cones in the autumn. Before they are planted, the hard seed coats are rubbed with sandpaper to help them grow quickly. The seeds are planted in paper containers and kept in a nursery to protect them from mice, birds and frost. Young trees are called saplings. They stay in the nursery for three years.

Trees are often planted by hand.

Before saplings are planted out, the soil is prepared with a digger or plough. The trees are planted close together to help protect them from the wind. Sometimes a fence is put up to stop deer or rabbits from nibbling the saplings.

When trees have grown big enough, they are cut down.

Conifers are cut down when they are 50-70 years old. Broad-leaved trees are left until they are 100-150 years old. Some trees are cut down by a woodcutter, or lumberjack, using a chain saw. Others are cut down with a harvester machine.

Each year a tree grows a new layer of wood. The rings inside a tree trunk show each year’s new growth. If you count the rings you can find out how old the tree is. This tree is probably older than you.

Knots show where a branch grew out from the tree trunk.

The fibres make a pattern of lines called the grain. If the lines are close together, the wood is a hardwood. Broad-leaved trees have hardwood which is close-grained. If the lines of the grain are wider apart, the wood is open-grained or softwood. Conifers produce softwood.

Some wood is very strong.

Trees and other plants make a substance called cellulose. Cellulose forms into strands which mat together and make up the walls of tiny cells inside the tree. The cellulose is very important as it makes wood strong.

This board game is made from different colour woods.

Each type of tree has different coloured wood. Pine trees have a pale wood and walnut has a dark brown wood. A mixture of different colours of wood is sometimes used to decorate furniture.

The wood we use comes from two types of trees. One type is called broad-leaved trees and the other type is called conifers. Broad-leaved trees grow slowly and have hard wood. Conifers grow much faster and their wood is usually softer.

This oak tree is over 100 years old.

Broad-leaved trees such as oak and maple have wide leaves. Most broad-leaved trees are deciduous, which means they lose their leaves in the autumn. Broad-leaved trees usually grow in mild climates, but some grow in tropical rainforests. Timber from broad-leaved trees is known as hardwood.

Most of our wood comes from conifers.

Conifer trees have needle-like leaves and grow well in cold conditions. They are grown in large forests called plantations. Plantations are like tree farms. The timber from conifer trees is called softwood.

Wood from conifers is used to build houses.

Fast growing softwood trees like Scots pine are used to make telegraph poles and the frames for some houses. Timber from slow growing hardwoods, such as oak, is used for making furniture.

Wood is an amazing natural material. It is used every day all over the world. Wood is used to make many things. It was even used to make this book you are reading!

Wood is found under the bark of trees.

Wood comes from inside the trunks and branches of trees. The outside of a tree is covered with bark, which is like the tree’s skin. The bark protects the wood on the inside from being attacked by insects, fungi and animals. Each kind of tree has its own special bark pattern, texture and colour.

The dolls and the violin are made from wood.

Wood is strong, springy and warm to the touch. It can be cut, carved, shaped and coloured. Wood is used to build houses and to make furniture. Many musical instruments are made from wood.

Continue reading “What is wood?”