tree

You can kill a tree just by removing a ring of bark on the main trunk

Tree Girdling, also called ring barking or ring-barking, is the complete removal of a strip of bark (consisting of cork cambium, phloem, cambium and sometimes going into the xylem) from around the entire circumference of either a branch or trunk of a woody plant. Girdling results in the death of the entire tree over time. A branch completely girdled will fail and when the main trunk of a tree is girdled, the entire tree will die, if it cannot regrow from above to bridge the wound.

Among the causes of girdling are human practices, including forestry, horticulture, and vandalism. Foresters use the practice of girdling to thin forests and orchardists use it as a cultural technique to yield larger fruit. Girdling can also be caused by herbivorous mammals feeding on plant bark and by birds and insects, both of which can effectively girdle a tree by boring rows of adjacent holes.

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