Reference Terms
from Wikipedia, the free encyclopedia


Wood has been an important construction material since humans began building shelters, and remains in plentiful use today.

A tree increases in diameter by the formation, between the old wood and the inner bark, of new woody layers which envelop the entire stem, living branches, and roots.

Where there are clear seasons, this can happen in a discrete pattern, leading to what is known as growth rings, as can be seen on the end of a log.

Note:   The above text is excerpted from the Wikipedia article "Wood", which has been released under the GNU Free Documentation License.
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May 27, 2017

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