There's Life In Dead Trees

Most people realize how important living trees are to the environment. But what about dead trees? In the last century, foresters believed that dead trees were useless and should be cut down. Today we know that dead and dying trees are very important to the health of a forest. In nature, everything is recycled with the help of many forms of life.

Like people, many trees die of old age. Trees also are killed by storms, fire, disease, or by being cut down. Trees can live longer than any other plant or animal on earth. Standing dead trees more than six metres (21 feet) high are called "snags." Snags are home to many insects, birds, and other animals. Woodpeckers drill holes in snags in which they make nests to raise their young. When woodpeckers leave these holes, other birds use them - owls, flycatchers, bluebirds, chickadees, wrens, nuthatches, starlings and wood ducks, to name a few. The birds that nest in dead trees eat many insects that could harm or kill the living trees growing in the forest. Many other animals use old tree-holes as homes - chipmunks, flying squirrels, mice and raccoons. Even bears use big hollow trees as dens, and eat insects that live in trees. Tree-homes offer protection from bad weather and enemies. They are also safe, warm places for these animals to raise their young.

When a dead tree finally falls, nature's "clean up crew" moves in. Termites and beetle larvae (wormlike insect babies) chew tunnels in rotting wood so bacteria, fungi and slime molds can move in. Slime molds are a type of fungus that eats dead wood and leaves. Fungi lack chlorophyll and therefore cannot make their own food like green plants do. Slime molds creep along over rotting logs and leaves, absorbing bits of them as food. Because they can move, slime molds are different from other fungi.

These insects and plants soften the hardwood so other insects can eat it. Some beetles, ants, slugs, centipedes, wood lice, and snails then chew on this softwood and excrete it as waste. Earthworms mix this deadwood waste with the soil. Finally, the elements that once were part of the tree, such as carbon, nitrogen, and phosphorus, become nutrients in the soil. The new trees need these nutrients to help them grow. This process is called decomposition, and it is very important to the health of the forest.

When loggers cut down trees, they remove them from the forest. These trees do not decompose, and the nutrients in them are not replaced in the soil. In forests where logging takes place, new trees are planted, but most do not grow old and decay - they are cut down first.

A few centuries ago, 850 million acres of forest covered North America. Today, 90% of those forests have been cut down. The forests that remain are called "old growth" forests. Most of the forests we see today are young forests - forests replanted to be harvested as crop in 30 or 40 years. The problem is forests replanted with just one tree species do not support a mixed variety of wildlife.

If we allow them to grow old, trees will continue to provide homes for helpful birds and animals, and decomposition will continue to return important nutrients to the soil. Only then can the future health of our forests be saved.

Because we all use paper and wood products daily, we must make sure there are forests left to provide homes for animals.

How Can You Help?

Use less paper. Buy paper made from recycled paper when possible, and recycle whatever paper you can.
Share and then recycle comic books, paperbacks, magazines, newspapers, and newsletters.
Plant some trees every year.
Leave some dead trees standing or lying on the ground around your home, providing the trees are not a hazard.
Let a natural wilderness area grow in your backyard to provide food for birds and many other creatures.
Learn about forests. Examine old logs, look for insect chewing marks, woodpecker holes, slime molds and more. Life on a dying tree is actually very exciting. Be sure you do not disturb the animals' homes. Look carefully but do not tear a log apart.

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