Overweight & Obesity

Study to examine health benefits of outdoor preschools

As preschoolers across the nation head into classroom buildings for the start of the school year, more than 300 Seattle area children enrolled in the Tiny Trees Preschool will get to spend their time learning outside—rain ...

Psychology & Psychiatry

Trees an oasis of mental well-being

(HealthDay)—City dwellers who live on tree-lined streets might be happier and healthier for it, a large new study suggests.

Medical research

Relieving two headaches with one process

With a new method to synthesize a popular pain-relieving medication from plants rather than fossil fuels, researchers at the Great Lakes Bioenergy Research Center have found a way to relieve two headaches at once.

Genetics

First US murder trial using DNA, family tree evidence

A truck driver implicated by his DNA and family tree in a double murder more than 30 years after the crime will face trial this week in the first case using a revolutionary investigative technique.

Psychology & Psychiatry

A 5-minute recipe for stress relief

(HealthDay)—Whether it comes from demands at home, a slow commute or monthly bills, it's hard to escape stress. Beyond affecting your mood, it can play havoc with your health, from lost sleep and stress-eating to weight ...

Medical research

Small shrew could make a big difference in dry eye research

Breakthroughs in health care can come from unusual places. Jianzhong Chen, Ph.D., assistant professor in the University of Alabama at Birmingham's School of Optometry, and his colleagues may have discovered a new one for ...

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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