The main parts of a tree are the roots, the trunk and the leaves.

The tree attaches itself into the ground with its strong roots. They can reach several meters down into the ground. Horizontally, the roots can stretch over tens of meters away from the tree's trunk. By doing so, the branching roots create a vast underground network. 

The tree uses its roots to collect water. The tree also receives nutrients that have dissolved into the water. The most important nutrients for trees are nitrogen, phosphorus and potassium. Plants need these nutrients to grow and thrive. 

The trunk of the tree reaches up towards the sky. By growing its trunk, the tree makes sure that its leaves have enough access to sunlight. The trunk is made of a durable material. The trunks of some trees can grow over 100 meters tall! 

Narrow tubes run inside the tree's trunk, connecting its leaves and its roots. Water and nutrients travel through these tubes into the leaves of the tree. 

The route of water in a tree is therefore: roots → trunk → leaves.

The leaves of the tree produce all the energy that it needs. They do this in a process known as photosynthesis. 

There are many different kinds of trees in the world. The leaves of broadleaf trees are large and flat. The leaves of broadleaf trees grow during the spring and fall during the autumn. 

The needle-like leaves of coniferous trees remain attached through the winter. Despite this, these leaves only photosynthesise during the summer months.