I saw a surprising photograph on the internet that I am including in this post. The photograph shows a large tree on the right that is connected at two sites by lateral branches with a smaller tree on the left that lacks a link to the ground. The tree on the left doesn’t have any roots, yet it seems to be alive (it has leaves) because it is presumably maintained by the tree on the right.
This phenomenon where a tree forms a connection with another is called inosculation. This happens when parts of trees grow in contact with each other and the abrasion produced overtime by the movement of one part against the other due to, for example, the wind blowing, wears out the outer layer of bark. This puts the inner cambium layers (where tree growth takes place) in contact with each other. These layers will fuse and the bark will reform around them resulting in a connection. In essence inosculation is a type of grafting. The resulting trees in nature are called “marriage trees” or “husband and wife” trees.
Inosculation is used in the art of tree shaping, which is also known as tree sculpture, arborsculpture, ornamental grafting, or pleaching. This is the art of making trees grow in unusual shapes, which requires a lot of patience, time, and work. In the United States one of the most notable practitioners of this art was Axel Erlandson who during his lifetime grew several dozen trees, which he called “circus trees”, into amazing shapes. When I visited the American Visionary Art Museum (AVAM) in Baltimore, Maryland, I got to photograph the remains of one of these trees called “The Telephone Booth Tree”.
The AVAM photographs belong to the author and can only be used with permission. I have not been able to figure out who took the photograph of the large tree propping up the smaller tree or if it is in the public domain. If this photograph belongs to you, please let me know, and I will follow your instructions.