Sunday, November 26, 2006


A tree is a plant appearance that occurs in many special orders and families of plants. Trees thus show a wide selection of growth form, leaf type and shape, bark personality, reproductive structures, etc.

The earliest trees were tree ferns and horsetails, which grew in huge forests in the Carboniferous Period; tree ferns still live, but the only surviving horsetails are not of tree form. Later on, in the Triassic Period, conifers, ginkgos, cycads and other gymnosperms appeared, and subsequently flowering plants in the Cretaceous Period. Most species of trees today are peak plants and conifers. The listing under gives examples of many well-known trees and how they are naturally classified.

A small group of trees growing jointly is called a grove or copse, and a landscape enclosed by a dense growth of trees is called a forest. Numerous biotopes are defined largely by the plants that inhabit them; examples are tropical forest and taiga. A landscape of trees spread or spaced across grassland is called a savanna.

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