What is Tree?
[[File:Aspen-PopulusTremuloides-2001-09-27.jpg|thumb|220px|The trembling [[aspen]] in its autumn colours]] [[File:20131204 Istanbul 002.jpg|thumb|Trees in [[Istanbul]], [[Turkey]]]] [[File:Enterolobium cyclocarpum in Guanacaste.jpg|thumb|right|200px|[[Strangler fig]] tree in [[Costa Rica]]. Locally known as ''Guanacaste'']] [[File:Ficus watkinsiana on Syzygium hemilampra-Iluka.jpg|thumb|200px|...and this shows how the strangler fig grows]] A '''tree''' is a tall [[plant]] with a trunk and branches made of [[wood]]. Trees can live for many years. The oldest living tree found is about 5,000 years old. The oldest tree from the UK is about 1,000 years old.{{Verify source}} The four main parts of a tree are the [[root]]s, the [[Trunk (botany)|trunk]], the [[branch]]es, and the [[leaf|leaves]]. Trees are a wide variety of plant species that have independently evolved a trunk and branches as a way to tower above other plants to compete for sunlight. The roots of a tree are usually under the ground. However, this is not always true. The roots of the [[mangrove]] tree are mostly under water. A single tree has many roots. The roots carry [[nutrients]] and [[water]] from the ground through the trunk and branches to the leaves of the tree. Leaves can also breathe in air. Sometimes, roots are specialized into [[aerial root]]s, which can also provide support, as is the case with the [[banyan]] tree. The trunk is the main body of the tree. The trunk is covered with [[bark]] which protects it from damage. Branches grow from the trunk. They spread out so that the leaves can get more sunlight. The leaves of a tree are green most of the time, but they can come in many colors, shapes and sizes. The leaves take in sunlight and use water and food from the roots to make the tree grow, and to reproduce. Trees and [[shrub]]s take in [[water]] and [[carbon dioxide]] and give out [[oxygen]] with sunlight to form [[sugar]]s. This is the opposite of what animals do in respiration. Plants also do some respiration using oxygen the w