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coast redwoods-series_grade_9-12

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coast redwoods-series_grade_9-12

  1. 1. What’s the Tallest Thing You’ve Ever Seen? GRADES 9-12 Coast Redwood Redwoods®
  2. 2. Where Are Coast Redwoods Found? Coast redwood forests are very rare and grow naturally only in a narrow 450-mile strip along the Pacific Ocean from central California to southern Oregon. More than tall trees, a redwood forest is a complex set of ecosystems made up of an astounding variety of living and once-living things. How Old Are They? Individual coast redwood trees can live for hundreds of years. In some areas of their range, they can live more than 2,000 years. The oldest known coast redwood tree was 2,200 years old. How Do Redwoods Reproduce? Redwoods are conifers, which means they have cones and needle-like leaves. A coast redwood cone is about 1 inch long and contains 14 to 24 tiny seeds about the size of a tomato seed. A single tree may produce millions of seeds in a year. Only a small percentage of the seeds actually germinate and grow into seedlings. Although coast redwoods can grow from seeds, they more commonly reproduce from sprouts. New trees can sprout from the roots of parent trees, from buds at the base of a tree or from a fallen tree. If a tree is cut or burned, a circle of trees may sprout from the stump, forming a “fairy ring” of new trees. Where Have Redwood Fossils Been Found? Redwood trees are true “living fossils.” As a genus, redwoods have existed seemingly unchanged for millions of years. Redwood fossils older than 144 million years have been found throughout the western United States and Canada and along the coasts of Europe and Asia. Close ancestors of the coast redwood were living when dinosaurs roamed the Earth. Coast redwoods prefer mild year-round temperatures with winter rain and heavy fog, a climate that was more common in earlier ages. The last ice age limited coast redwoods to their present range along the coast of northern California and southwestern Oregon. How would it measure up to a coast redwood tree? The coast redwood (Sequoia sempervirens) is the world’s tallest tree species and among the oldest living things. 10-Story BuildingCoast Redwood Giant Sequoia Apple Tree Mature coast redwood trees often reach more than 320 feet tall and many of the tallest known trees are more than 360 feet high. Coast redwoods can reach these heights because they are very resistant to disease and insects. The wood has a high level of tannic acid, which is toxic to most insects. These fascinating trees are named for the beautiful red color of their bark and heartwood. Photo:PhilSchermeister Coast Redwood California Pacific Ocean Oregon Coast Redwood Range
  3. 3. How’s the Weather Imagine standing at the base of a coast redwood tree. If you crane your neck and look up, you will just see the lowest branches some 10 stories above you. If you peer even higher up, through the distant branches and needles, you will hardly see the top of the tree, which can be higher than a 37-story building. Just how can a coast redwood get so tall? Trees continue to grow as long as they live — and coast redwoods can live more than 2,000 years. However, age alone cannot fully explain the redwoods’ vast height because they are not the oldest trees in the world. Some bristlecone pines in the White Mountains of California are more than 4,500 years old but usually only grow to about 60 feet. The coast redwoods’ environment plays a large part in why they grow so tall. These trees live where the soil is very rich in nutrients, where they are mostly protected from winds and where they receive lots of winter rain and summer fog. These conditions allow them to thrive and grow to great heights. Scientists now think that fog may be a critical reason for coast redwoods being so tall. Where the trees live, winters are very rainy, but there is very little rain the rest of the year. During the summer, however, a thick fog usually blankets the region. Redwood trees are able to intercept this dense fog in their crowns, where it condenses on their leaves. The trees use this fog in a number of different ways. First, the fog reduces the amount of water that the trees need because they lose less water through their leaves when it is foggy. Second, the trees can absorb the fog directly through the leaves, which is an especially important source of water for young trees. Finally, the condensed fog drips to the ground below the trees, where it soaks in for later use. With summer fog and winter rain, redwoods have water all year- round — this may be the most important reason for their great height. It’s in the Genes Redwoods have more chromosomes than most other cone-bearing trees, a fact that also may help them grow tall. Chromosomes are the part of the cell that carries genes. Conifers usually have 20 to 24 chromosomes, but redwoods have 66 or more. That is because redwoods have six copies of each chromosome, while most conifers have two copies of each. How does the number of chromosomes help the redwoods grow? With six copies of each chromosome, a single tree can have several alternative forms of a gene. For example, a tree may have two or even three different gene codes for an enzyme that helps the tree fight a certain disease. This means that if a pest or disease tries to attack the tree, the tree has a greater chance to protect itself. The healthier the tree, the more likely it is to grow. Photo:PhilSchermeister Up There?
  4. 4. VarietyIs the Spice of a Forest’s Life Many other tree species can live among the redwoods. Examples of these are Douglas-firs, western hemlocks, grand firs, Sitka spruces, tanoaks, madrones, maples and California bays. Rhododendrons, dogwoods and ferns thrive underneath the trees, as do poison oak, huckleberry, hazel and many flowering herbs. Redwood forests also support a large number of animal species, including more than 200 different vertebrates. Frogs, salmon, toads, salamanders, snakes, lizards, marbled murrelets, sparrows, blackbirds, wood warblers, bats, squirrels, chipmunks, mice, weasels, bear, deer and elk all can be found among redwoods. Many people think a forest is just a bunch of trees that all look alike. But a healthy forest is really about variety. An ancient coast redwood forest has a mixture of different trees and shrubs that are many different ages and sizes. This allows for a range of different animals and plants to live in the forest. The greater the variety, the more diversity — and a healthy community depends on diversity. Photo:HowardKing Photo:RuskinK.Hartley Photo:RuskinK.Hartley eister Photo:PhilSchermeister
  5. 5. Compare the amount of tree cover in your neighborhood to that in a nearby park or nature area and to a redwood forest. Find aerial maps of the areas ( and Google Earth are possible free sources) and use grid paper to estimate the percentage of each area that is covered by trees. How do the areas compare? What does your community do to maintain its “urban forest”? Explore Even redwood soil contains a wide variety of different organisms. Surprisingly, soil can be found high in the branches of the trees. This soil comes from the huge quantity of leaves that the tree sheds each year, some of which collect at the base of large branches and decompose into soil. In studying these soil mats, scientists have found an astonishing number of plants and animals, including beetles, crickets, earthworms, millipedes, salamanders, various fungi, ferns and even young trees — all living hundreds of feet in the air. The plants and animals in the redwood forest are interdependent in many different ways. Scientists now understand that these complex interactions are crucial to the survival of the ancient redwood forest. When roads, housing developments, power lines, logging or trails isolate redwoods from other parts of the forest, they are less likely to thrive. This is a concern because most of the remaining ancient redwood forest is made up of isolated groves. Each element of the ancient forest is connected to others in ways that we may never fully understand. To save the remaining ancient redwoods, it is clear that we have to save the forest as a whole instead of just saving individual trees. Photo:PhilScher Photo:PhilSchermeister Photo:USFWS Photo:©BrandonCole
  6. 6. Get Active About Save the Redwoods League Saving the Coast Redwood Forest The native people of California treated the majestic coast redwoods with reverence. They did not usually cut down redwoods, but used fallen trees to make planks for houses and hollowed-out logs for canoes. There were 2 million acres of ancient coast redwoods in California and Oregon before the 1849 Gold Rush. Since then, redwoods have been logged for lumber and to make way for roads, houses and other buildings. At first, there were so many trees that people did not worry about cutting them down. Today less than 5 percent of the original ancient forest remains. Save the Redwoods League was founded in 1918 to protect these awe-inspiring trees. Over the years, the League has purchased many thousands of acres of forestland and has helped to develop dozens of state and national parks and reserves. Much work remains to ensure that future generations can enjoy these magnificent forests. Thousands of acres of ancient redwood forest remain on private land and could still be logged for lumber or for real-estate development. The League also considers climate change a serious threat to coast redwoods. Many scientists are concerned that rising temperatures and changing weather patterns will reduce the coastal fog on which redwoods depend and may further limit the range of redwood forests. Together we are studying the potential effects of climate change to determine how best to protect these amazing ecosystems. Since 1918, Save the Redwoods League has saved redwood forests so that people can be inspired by these precious natural wonders — now and in the future. The League and its partners help people of all ages experience these majestic trees through the forestlands we have helped protect and restore, the many education programs we sponsor and our Web site. Learn More Visit the Save the Redwoods League Web site at Find books about redwood trees or ancient forests at a local library. Inspire Others Research different organizations that work on forest issues and join one you like. Send your redwood art, poetry, photos or memories to Save the Redwoods League, and we might post them on our Web site! Visit a Park Plan a trip with your family to a park or reserve in the ancient redwood forest. See the Save the Redwoods League Web site at for information on redwood parks and reserves. Reduce, Reuse, Recycle Trees are logged because there is a demand for wood and paper products. You can help reduce the demand by reusing and recycling paper, cardboard and wood at home and at school. Plant a Native Tree Learn what kinds of trees are native to your area and choose one to plant. Find a location for the tree that will allow it to grow for many years. If you can’t plant a tree, find a local group that will plant one for you. Photo:HumboldtHistoricalSociety 114 Sansome Street, Suite 1200 San Francisco, CA 94104 (415) 362-2352