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tree line

noun Unabridged
Based on the Random House Dictionary, © Random House, Inc. 2015.
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Examples from the web for tree line
  • It disappeared over a tree line and into the forests beyond.
  • Teahouse keepers and porters now scurry ever farther down-valley to retrieve timber from the descending tree line.
  • Breeding: stunted boreal bogs and in open country near tree line, especially in willows and alders.
  • The zigzag relay is necessary to gain enough elevation for the signal to clear the tree line.
  • We were climbing now, gaining in elevation and nearing the tree line.
  • Even below tree line, campfires are often prohibited because of concerns about forest fires.
  • Above the tree line, small pikas live in the rocky crevices of the mountains.
  • Visitors arrive at the museum's entrance at the top of the ravine and descend below the tree line into the main lobby.
  • Pets may walk along the sidewalks and are allowed to go to the tree line of the swimming beaches.
  • Most of the area below the tree line remains forested.
British Dictionary definitions for tree line

tree line

the zone, at high altitudes or high latitudes, beyond which no trees grow. Trees growing between the timberline and the tree line are typically stunted
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition
© William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins
Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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tree line in Science
tree line  
See timberline.
The American Heritage® Science Dictionary
Copyright © 2002. Published by Houghton Mifflin. All rights reserved.
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Encyclopedia Article for tree line


upper limit of tree growth in mountainous regions or in high latitudes, as in the Arctic. Its location depends largely on temperature but also on soil, drainage, and other factors. The mountain timberline always would be higher near the Equator than near the poles if it were not for the abundant rainfall in equatorial mountainous regions, which lowers the air temperatures. The timberline in the central Rockies and Sierra Nevadas is around 3,500 metres (11,500 feet), whereas in the Peruvian and Ecuadorian Andes it is between 3,000 and 3,300 metres (10,000 and 11,000 feet). In much of the central and southern Rockies there is a double timberline: the usual high timberline below which there is a belt of normal tree growth; and then a low timberline below which no trees grow because of low precipitation and high temperatures.

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Encyclopedia Britannica, 2008. Encyclopedia Britannica Online.
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