The quest to save the banana from extinction

Panama disease, an infection that ravages banana plants, has been sweeping across Asia, Australia, the Middle East and Africa. The impact has been devastating. In the Philippines alone, losses have totalled US$400m. And the ...

Tree dens play a critical role in panda lifestyle

In a paper recently published in the journal Biological Conservation, an international team of conservationists highlights the importance of tree dens for pandas raising infants in native habitats. The study, conducted in ...

The high price endangered animals pay for charisma

"Wanted: beautiful, intelligent companion well-versed in the art of conversation." It's a familiar story, but don't expect a fairy-tale ending. In this instance, we're talking about a transaction that condemns one of the ...

Image: the Egg Nebula

The Egg Nebula is a preplanetary nebula, created by a dying star in the process of becoming a planetary nebula. Planetary nebulas have nothing to do with planets – the name arose when 18th century astronomers spotted them ...

Algorithms to enhance forest inventories

An EPFL doctoral student has come up with methods to map out forests more effectively using aerial remote sensing, in support of on-the-ground forest inventories.

U.S. forests changes are double-edged sword for environment

Climate change, nitrogen deposition and fire suppression are leading to shifts in the types of trees that dominate American forests. These changes will have environmental consequences, potentially positive and negative, according ...

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Tree

A tree is a perennial woody plant. It is most often defined as a woody plant that has many secondary branches supported clear of the ground on a single main stem or trunk with clear apical dominance. A minimum height specification at maturity is cited by some authors, varying from 3 m to 6 m; some authors set a minimum of 10 cm trunk diameter (30 cm girth). Woody plants that do not meet these definitions by having multiple stems and/or small size, are called shrubs. Compared with most other plants, trees are long-lived, some reaching several thousand years old and growing to up to 115 m (379 ft) high.

Trees are an important component of the natural landscape because of their prevention of erosion and the provision of a weather-sheltered ecosystem in and under their foliage. Trees also play an important role in producing oxygen and reducing carbon dioxide in the atmosphere, as well as moderating ground temperatures. They are also elements in landscaping and agriculture, both for their aesthetic appeal and their orchard crops (such as apples). Wood from trees is a building material, as well as a primary energy source in many developing countries. Trees also play a role in many of the world's mythologies (see trees in mythology).

This text uses material from Wikipedia, licensed under CC BY-SA