Tractable Trees

Tree Hoop, Pagosa Springs - April 2024

​One afternoon this past spring my parents and I were enjoying the fresh air and warm sunshine in the wooded canyon behind their Little Red Cabin, known in the family as the LRC. We came upon the hooped tree pictured above. Wow! We hadn’t noticed it on previous hikes, and it seemed rather magical. How did this happen?

It is possible that one side of that particular branch was damaged, and did not grow at the same rate as the other side, creating the asymmetry that caused the branch to grow back towards the ground. Another possibility is that that low branch was weighted by snow long enough that the branch did not resume growing skyward. It continued to grow downward, causing the bend in the main trunk before the tree righted itself to grow straight up once again.

My research did not turn up a definitive reason for the hooped branch of our tree. Regardless of the cause, this hoop - and what I found poking around online -  is a testament to the resilience and tractability of trees. 

Trees have three main parts: crown, trunk and roots. The trunk conducts nutrients, the foliage on the branches (boughs or twigs) conducts photosynthesis, and the roots provide nutrients from the soil. All parts of the tree grow: roots, branches and trunk, and are quite versatile over time and with necessity. I found this article’s illustrated trunk cross-section interesting:  Arborist Now.com: The Basic Anatomy of a Tree

Roots have hair-like projections which serve to stimulate growth in the current direction, or stop growth if an obstacle is encountered. The root hairs accomplish this by a protein at their tip; this protein causes uptake of calcium for growth, and the cycle continues. The roots can grow out to a distance twice the height of the tree. If the root hairs hit an object, the calcium uptake - and thus the growth - come to a halt. All About Trees.com: Trees Can Grow Around Obstacles

Edaphoecotropism, also known as “stress avoidance” is the ability of living tissues to grow around things. The engulfing occurs as the roots and woody tissue of the tree grow towards areas of least stress, thus surrounding or “eating” the item. The objects do not hurt the tree; in fact some articles indicate that the incorporated objects help strengthen the tree.

Here are some amazing photos of objects like trucks and fences swallowed by trees: Scenic Hudson.org: Trees that Eat Things. My favorite from this article is the bike tree. A young man headed off to World War I left his bike against the tree, but never retrieved the bike. The tree, in its edaphoecotropic (according to Google this word does not exist, I believe it should) manner, grew up and around the bike, so that the bike is now well above the ground, a part of the tree.

I loved the playset in my grandparent’s backyard in Glen Burnie, Maryland, between two towering oak trees. It had a slide that the squirrels would careen down over and over, having a marvelous time. It also had a swing. Long before my time, and the ends of the pole to which the swing was attached had been stuck in the oak trunks. Over time the trunks had grown around and onto the pole a few inches - there’s that edaphoecotropism again. The trees growing like this was a wonder to me, and I never tired of looking at those guardian oaks keeping my swing safe.

​Sources/Learn More
Arborist Now.com: The Basic Anatomy of a Tree

All About Trees.com: Trees Can Grow Around Obstacles

Scenic Hudson.org: Trees that Eat Things

Riparian Habitat Restoration.ca: post explaining edaphoecotropism (scroll to middle of article)

Photo courtesy of Tom Denny