Solar activity reconstructed over a millennium

An international team of researchers led by ETH Zurich has reconstructed solar activity back to the year 969 using measurements of radioactive carbon in tree rings. Those results help scientists to better understand the dynamics ...

Aphids suck: Invasive aphid found on Danish apple trees

The spirea aphid, Aphis spiraecola, an invasive pest, has been discovered for the first time in Denmark by University of Copenhagen researchers. The extent of its current distribution remains unknown, but in time, it could ...

Forests go into growth 'overdrive' to recover from drought

One in 12 people could face severe drought every year by 2100, according to a recent study. And water stored on two-thirds of the Earth's land surface will shrink as the climate warms. As plant ecologists, we're concerned ...

How hitchhiking worms choose their vehicles

Tiny worms that live inside fig trees use the fig wasp as a 'vehicle' to hitch rides from one tree to another by crawling into the wasp's gut without harming it. This relationship has existed for millions of years. But how ...

Study highlights the role of forest fuels amid a warming climate

California's drought of 2012-2016 killed millions of trees in the Sierra Nevada—mostly by way of a bark beetle epidemic—leaving a forest canopy full of dry needles. A study published from the University of California, ...

Knowledge of cycad branching behavior improves conservation

Research on cycad trees in Colombia, Guam, and the Philippines has illuminated how knowledge of their branching behavior may benefit conservation decisions for the endangered plants. In a study published in the December issue ...

Scientists discover bizarre new mode of snake locomotion

A team of researchers from Colorado State University and the University of Cincinnati have discovered a new mode of snake locomotion that allows the brown tree snake to ascend much larger smooth cylinders than any previously ...

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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