Not all dangerous trees look like they are about to fall. In fact, many of the most hazardous trees appear healthy on the outside while hiding major structural issues within. Cracks, leaning trunks, and internal rot are three subtle but serious signs that a tree may be on the verge of collapse. Trees 101 would like to uncover some of the hidden signs of a tree that needs to be removed quickly.
Cracks in the Trunk or Major Limbs
Cracks might look like minor imperfections, but they are actually one of the most alarming signs of a weakened or unstable tree. These splits typically appear in the main trunk, large limbs that meet the trunk or in vertical sections of major branches. Cracks are a sign that the tree is under stress or has already suffered internal damage. Over time, a cracked tree can suddenly split or break apart, especially during storms or high winds.
• Deep vertical or horizontal splits in bark.
• Cracks accompanied by sap oozing or fungus.
• Cracks that grow wider over time.
These are often urgent red flags for removal or at least professional assessment.
Leaning Trees
A tree does not have to be falling over to be dangerous. A noticeable lean, especially one that’s new or worsening, can be a serious structural issue. When leaning becomes a problem:
• A lean greater than 15 degrees is often considered hazardous
• Recent storms, flooding, or root disturbance can trigger sudden leaning
• If the soil around the base is cracked or heaving, the root system may be failing
Trees that lean toward structures, roads, or power lines require immediate attention and often need removal to prevent property damage or injury.
Internal Rot and Decay
Rot can quietly hollow out a tree from the inside, making it structurally unsound. Often, trees continue to grow outward while decaying at their core creating the illusion of health. Signs of internal rot can include:
• Mushrooms or fungal growth on the trunk or at the base.
• Soft, crumbly, or discolored wood.
• Large cavities or hollow sounds when tapped.
• Peeling bark and dead sections of the canopy.
A tree with internal rot may look solid but can collapse with very little warning. If the rot affects more than 30% of the tree, removal is usually recommended.
Other Signs to Watch For
• Dead or hanging branches high in the canopy.
• Roots lifting or showing signs of decay.
• Sudden loss of leaves in one section of the tree.
• Heavy insect activity around the trunk or roots.
These subtle signs may indicate that a tree is at risk of failing, especially during extreme weather.
Why You Shouldn’t Wait
Delaying removal can result in costly damage to homes, fences, vehicles, and utility lines. They can cause serious injury to people or pets and emergency service calls after a collapse which are usually more expensive. Removing a hazardous tree before it falls is always safer and more cost-effective than dealing with the aftermath.
Call a Professional Arborist
If you are unsure whether your tree is at risk, don’t take chances. A certified arborist can conduct a tree health and safety inspection, identify risks you may have missed and recommend pruning, cabling, or removal when needed.
Tree Trimming, Pruning, Removal & More | Trees 101 Based in Houston, Texas
Cracks, leaning, and rot are signs your tree may already be compromised. The longer you wait, the higher the risk. If you suspect a tree on your property is unsafe, it is time to take action. Contact Trees 101 for a professional evaluation or emergency tree removal services today.
