Tree

A tree is a plant consisting of root?s, a trunk?, branch?es, twig?s and leaf?s. In analogy with skin, a tree has bark? to protect it against infection?s and fungus attacks, and also to transport nutrients and water to the growth zones along the branches and leafs. A small group of trees growing together is called a grove? whereas a lrge population of trees is called a forest.

The roots of a tree stand embedded in earth and extract water and nutrients from the surrounding soil?. Above ground, the trunk gives height to the leaf-bearing branches in order to compete for sunlight. The branches spread to present the largest possible leaf surface to the sun.

Trees can grow to over 100 meters of height and become several millennia old if circumstances are optimal. A smaller variant of tree (one without a trunk) is called a shrub?.

Several types of biotopes are defined largely by the trees that inhabit them: The rainforest? and the taiga are among the most important.

Trees often serve as important symbols in mythologies and religions. Examples are Yggdrasil in the Norse Mythology and the [Tree of Knowledge]? of christianity.

Commonly known variants of trees are:

• Aspen?
• Beech?
• Birch?
• Ebenholtz?
• Larch?
• Eucalyptus?
• Mahogany?
• Mangrove?
• Maple?
• Oak?
• [Palm tree]?
• Pine?
• Redwood?
• Spruce?