Portal:Trees

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Trees

$5 tree.JPG

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. They 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).

Selected article

Krummholz or Krumholtz formation (German: krumm, "crooked, bent, twisted" and Holz, "wood") — also called Knieholz ("knee timber") — is a particular feature of subarctic and subalpine tree line landscapes. Continual exposure to fierce, freezing winds causes vegetation to become stunted and deformed. Under these conditions, trees can only survive where they are sheltered by rock formations or snow cover. As the lower portion of these trees continue to grow, the coverage becomes extremely dense near the ground.

Common trees showing Krumholtz formation include Balsam Fir, Red Spruce, Black Spruce, Subalpine Fir, Subalpine Larch, Engelmann Spruce, Limber Pine, and Lodgepole Pine. Instances of the Krumholtz form of Black Spruce, Picea mariana, are found in the northern Canadian Boreal forests. Krumholtz-form Black Spruce and Balsam Fir are abundant in the Alpine Transition Zone of the White Mountains of New Hampshire.

Selected biography

Two Leg Tree

Axel Erlandson (December 15, 1884 – April 28, 1964) was a Swedish American farmer who shaped trees as a hobby, and opened a horticultural attraction in 1947 advertised as "See the World's Strangest Trees Here," and named "The Tree Circus."

The trees appeared in the column of Robert Ripley's Believe It or Not! twelve times. Erlandson sold his attraction shortly before his death. The trees were moved to Gilroy Gardens in 1985. Read more...

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Did you know?

Saalfeld Easter egg tree with 9200 eggs, taken March 24, 2009

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