There are more than 40,000 kinds of trees in the world. T ey grow in deserts, forests, meadows, and swamps. T ey grow on lake and ocean shores. T ey are big and small. No matter what they look like or where they
grow, all trees have the same parts. Roots pull up water and nutrients from the soil. Leaves make food from the sun. Bark protects them from insects and other harm. Branches and trunks support the tree and push it closer to sunlight. Trees are amazing living things.
Circle of Life
Like every living thing, trees have a life cycle. For example, high up in the White Mountains of California, sits an old, old tree. It’s been up there awhile—almost 5,000 years. It looks mostly dead with its twisted, broken limbs. People have named this bristlecone pine aſt er the biblical Methuselah who lived a long life. Methuselah is a conifer, or evergreen. Evergreens have special leaves and fl owers. T e leaves are leathery, green needles. T ey are tough and can withstand long periods without water. Instead of typical fl owers, evergreens have cones. Male cones make pollen, which releases into the wind. When the pollen reaches a female cone, seeds are produced. T e cone opens up, and the seeds fall to the ground. If conditions are good, the seeds sprout and grow into seedlings. T e seedlings grow into trees. T e trees make cones, and the cycle goes on.
Life After Death
When a tree dies, nothing is wasted. When it falls, it opens up an area for sunlight to reach the ground. T is allows awaiting seeds to sprout and take root. Some trees sprout right on the trunks of
fallen trees. T ey get nourishment from the tree as it rots. T ese fallen trees are called “nurse logs” and can oſt en sprout and support several growing trees.
A nurse log helps bring new life to the forest.
12 NATIONAL GEOGRAPHIC EXPLORER
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