Ridsdale C., White J., Usher C. Trees 2005
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In every society, trees provide food in the form of fruits and nuts, flavorings, and even edible flowers and leaves. Trees are the source of pharmaceuticals, as well as building timber and firewood. Their protective bark provides not only medicines but also resins, barkcloth, and cork. Their heartwood and water-transport systems produce long-lasting wood that is used to make furniture and the pulp for all modern books and newspapers. Trees provide the bases for the perfume industry. As a whole, forests harbor 75 percent of the world’s biodiversity. Trees intercept rainfall and gently release it in watersheds; they absorb carbon dioxide and replenish the air with oxygen. Trees are planted to restore degraded landscapes and provide forage for hungry animals. They protect coastlines and riverbanks. Some act as important shade trees and windbreaks; many others are grown as ornamentals. The original vegetation of much of the world was dominated by trees, and our ancestors were tree-living primates. Trees were the sources of food and medicine long before there was human consciousness. They still feature strongly in our human psyche: the forbidding forests of fairy tales, sacred groves, the Tree of Knowledge, and the Tree of Life—in Christianity, Jesus’s cross is often called “the Tree.” We have a great fascination with the tallest and oldest trees, which span generations of human lives. Their majestic gigantism is as attractive as that of the dinosaurs. Perhaps even more importantly, trees have provided the building materials and fuel for most civilizations, either as wood or fossilized as coal. More trees are used for fuel than construction—indeed, the North American peoples thought that the first European settlers could only have left their country because they had run out of firewood. Brought up in the English countryside before it was so mercilessly pressed into intensive agriculture, I was privileged, as a boy, to wander through woodlands and along hedgerows, learning for myself about the trees and the animals that they sheltered. Standing in a tropical rainforest, among the redwoods of California, the giant eucalyptus of southwestern Australia, or even the relic pine forests of Scotland, inspires an awe that few other experiences can. Not merely for economic reasons, then, should we do all we can to conserve these bases of civilization, trees, but because we rely on them so much for our spiritual welfare, too. Foreword What is a Tree? Tree Classification Tree Evolution Tree Structure How Trees Work Tree Reproduction Forests of the World Coniferous Forests Temperate Broadleaf Forests Tropical Broadleaf Forests Tropical Rainforests Barren Lands Identifying Trees Living With Trees Early People and Trees Tree Myths and Spirits Trees for Sustenance Trees for Wood and Building Trees for Paper and Pulp Other Products from Trees Trees for Amenity and Ornament Planting and Caring for Trees Forest Practice Trees and the Environment Tree Conservation Trees of the World Spore Trees Seed Trees Cycads Ginkgo Conifers Flowering Trees Primitive Angiosperms Monocotyledons Dicotyledons Glossary Tree Families Index Acknowledgments

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