Utilisateur:Rocherd/EssaiTrad3
Although "tree" is a term of common parlance, there is no universally recognised precise definition of what a tree is, either botanically or in common language.[1] In its broadest sense, a tree is any plant with the general form of an elongated stem, or trunk, which supports the photosynthetic leaves or branches at some distance above the ground.[2] Trees are also typically defined by height,[3] with smaller plants from 0.5 to 10 m (1.6 to 32.8 ft) being called shrubs,[4] so the minimum height of a tree is only loosely defined.[3] Large herbaceous plants such as papaya and bananas are trees in this broad sense.[1][5]
The largest tree by volume is believed to be a giant sequoia (Sequoiadendron giganteum) known as the General Sherman Tree in the Sequoia National Park in Tulare County, California. Only the trunk is used in the calculation and the volume is estimated to be 1,487 m3 (52,500 cu ft). Also in California is the oldest living tree with a verified age. It is a Great Basin bristlecone pine (Pinus longaeva) called Methuselah growing in the White Mountains. It has been dated by drilling a core sample and counting the annual rings; it was considered to be 4,844 years old in 2012.[6] It is thought likely that other bristlecone pines exceed 5,000 years of age.[6] A little further south, at Santa Maria del Tule, Oaxaca, Mexico, is the tree with the broadest trunk. It is a Montezuma cypress (Taxodium mucronatum) known as Árbol del Tule and its diameter at breast height is 11.62 m (38.1 ft) giving it a girth of 36.2 m (119 ft). The tree's trunk is far from round and the exact dimensions may be misleading as the circumference includes much empty space between the large buttress roots.[7]
See also modifier
References modifier
- « What is a tree? », Smartphone tour, University of Miami: John C. Gifford Arboretum, (consulté le )
- Tokuhisa, Jim, « Tree definition », Newton Ask a Scientist (consulté le )
- Gschwantner, Thomas, et al.
- Keslick, John A., « Tree Biology Dictionary », (consulté le )
- Martin, Franklin; Sherman, Scott, « Agroforestry principles », Echo technical notes, (consulté le )
- Earle, Christopher J., « Pinus longaeva », The Gymnosperm Database, (consulté le )
- Earle, Christopher J., « Taxodium mucronatum », The Gymnosperm Database, (consulté le )
[[Catégorie:Écologie forestière]] [[Catégorie:Morphologie végétale]] [[Catégorie:Plante]] [[Catégorie:Arbre]]