Over the last decade or so, tree houses have enjoyed a resurgence in their popularity. And many of these modern tree houses are often amazing to behold: Some feature plumbing and electrical service, while others are large enough to serve as full-time residences. These definitely aren’t your grandpa’s tree houses.
It’s easy to see why tree houses have regained their popularity, but many modern homeowners are curious about the tree house’s effect on the tree. So, we’ll try to talk a little about tree houses and how to avoid harming the trees that support them.
Do Tree Houses Harm Trees? A Qualified Answer for a Common Question
It is difficult to make sweeping generalizations, and some tree houses do harm their hosts, but if properly conceived, designed, placed and constructed, tree houses can usually be installed without damaging the tree.
Every situation, tree and tree house is different, so it is impossible to make guarantees about the future of any tree. However, as long as you account for the stresses and burdens you are placing on the tree, you can usually design and install a tree house without dooming your beloved tree.
While you can install a tree house that peacefully coexists with your tree, you’ll need to be mindful of a few important principles to avoid causing harm.
- Use non-invasive attachment strategies to connect the house to the tree. You may occasionally see a 50-year-old tree house that was attached via nails or screws, but this is misleading – most trees are likely to die within a few years of being impaled with a truckload of metal hardware. Instead, opt for attachment strategies that do not require bark-penetration. Usually, this means using flexible or semi-rigid straps and adjusting them periodically to accommodate the tree’s growth.
- Only place tree houses in trees that are large enough to support them. Over-burdening a tree with a hefty house can lead to large cracks or even total failure. Additionally, from a tree-biology point of view, it also makes more sense to use the largest tree possible. Large, mature trees grow much less from year to year than younger trees do during their prime growing years, which will put less stress on the attachment points.
- Only select trees that are noted for having strong wood, and avoid those prone to limb drop. The reasons for doing so are obvious, but you’ll need to research the trees in your yard extensively to learn about their differing strengths. Alternatively, you can consult with a trained arborist, who can likely identify the weak- and strong-wooded species on your property at a glance.
- Give careful consideration to the tree’s location. Placing a substantial structure in a tree’s canopy can alter the way the tree responds to the wind. This can lead to weakened spots in the wood and eventual failure. Because exposed trees are often subjected to strong winds, they are best avoided in favor of those sheltered by other trees. Also, from a practical point of view, nearby trees will also help partially protect the tree house from heavy rain or strong sunlight.
- Whenever possible, consider using supplemental posts to help reduce the strain placed on the tree. Just because you want to build a house in a tree doesn’t mean that the tree has to do the heavy lifting. By adding a few support posts, you can make the tree house safer and better protect the tree.
- Spread the tree house’s weight across the tree in a balanced fashion. Not only is this important for safety reasons, but it will also help protect the tree’s structure and stability. While trees produce tension and reaction woods to help cope with unbalanced canopies, you should always strive to keep the canopy as balanced as possible.
- Use neutral or light paints or stains to finish the exterior of the tree house. Excessive heat can stress a tree and cause its water needs to grow exponentially, dooming even the most drought-tolerant trees to suffer. With this in mind, you’ll want to avoid painting your tree house a dark color, which will cause it to absorb more of the brutal summer sun.
- Avoid creating cavities where moisture can collect. If you trap moisture near a tree’s bark, bacteria and fungi are almost guaranteed of colonizing the area, leading to disease or decay. One way to help do this is by ensuring that the tree house extends several inches beyond the branches (creating an “overhang”) whenever possible. You can also install a roof with sufficient overhang to help reduce the water reaching these areas.
If you are considering placing a tree house in one of your trees, contact your friends at Trav’s Tree Services and let one of our trained arborists inspect the tree beforehand. That way, you’ll be able to avoid building your family’s tree house on a diseased or damaged tree.