What Is the Tallest Tree?

Trees are green plants. They have roots, stems, leaves, and seeds, just as other green plants do. Trees are also the oldest of all green plants. Some of the sequoia trees of the north-western United States are more than four thousand years old. This means they wete fully grown trees long before Columbus discovered America!

And trees are the biggest of all green plants. The tallest trees known to exist on earth are the giant redwoods of California. There is one tree there, growing in the Humboldt National Forest, that is believed to be the tallest tree in the world. It is called the Founder's Tree and is over 110 metres high!

Some authorities believe that long ago the eucalyptus tree of Australia may have been as tall as these California redwoods, but those growing today average fifteen metres shorter. Two other kinds of trees that come close to the redwood are the Douglas fir and the sequoia, some of which have grown over 91 metres tall.

The roots of a tree not only take water and mineral materials from the soil, but also hold the plant firmly in the ground. And with very large trees, it takes quite a bit of root system to hold the tree firmly. Did you know that the roots of trees take up nearly as much room under the ground as their tops or crowns do above?

Scientists have learned to tell the age of trees by counting rings in the wood. There are rings in the cross-section of most kinds of tree trunks. New wood is formed each year in a layer outside the old wood and beneath the bark. It is this layer that becomes the ring. Each ring in the wood of the trunk of a tree represents one year of the tree's life. The trunk gets bigger and bigger around as new rings or layers are added.

A tree adds rings not only to its trunk but to its branches and twigs, too. Some new length is added to the tip ends of the twigs and branches each year. Because growth in height takes place only at the tips of branches, the limbs of trees never move farther from the ground than they were in the beginning!