Tree
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For other uses,see Tree (disambiguation).
The coniferous Coast Redwood,the tallest tree species on earth.A tree is a large perennial woody plant,larger than a shrub.Though there is no set definition regarding minimum size,the term generally applies to plants that grow to at least 5-6 meters (15-20 ft) high at maturity[citation needed] and having secondary branches supported on a main stem or stems,called a trunk.Most trees exhibit clear apical dominance,though this is not always the case.[1] Compared with most other plants,trees are long-lived,some of them getting to be several thousand years old and growing to up to 115 meters (375 ft) high.
Trees are an important component of the natural landscape due to their prevention of erosion and the provision of a specific weather-sheltered ecosystem in and under their foliage.Trees,through the process of photosynthesis,play an important role in producing oxygen and reducing carbon dioxide in the atmosphere; they also moderate ground temperatures through their shading effect.They are also significant elements in landscaping and agriculture,both for their aesthetic appeal and their orchard crops (such as apples).Wood from trees is a common building material.Trees also play an intimate role in many of the world's mythologies (see trees in mythology).