What are the largest plants?

Can you climb a maize plant or a tulip? Can you swing from a daisy? Of course not! But a tree is a different matter entirely.

Trees are tall, sturdy plants with woody stems called trunks. Branches grow from the trunk, usually quite far off the ground. It’s the trunk that makes a tree so strong. The trunk supports the tree.

The trunk also has several layers, each with an important job to do. Tree trunks are covered with a tough outer skin. Most trees have a hard, dry skin called bark. The bark protects the soft inside part of the tree. The next layer carries food made by the leaves to other parts of the tree. Next to this layer is the part of the trunk that makes the bark and new wood. Further inside is the wood. Some wood carries water around the tree. The inner wood helps support the tree.

In regions where trees make a new layer of wood once a year, the layers form a series of rings. After the tree has been cut down, each year’s layer of wood can be seen as a ring. A tree with 50 rings has lived for 50 years. The rings also reveal the tree’s life story. Narrow rings show that there was not much water or sunlight that year. Wider rings mean more water and sunlight were available, and more growth occurred.