Dead or hanging branches – Dead limbs are unpredictable and can fall without warning, even on calm days. The International Society of Arboriculture notes that deadwood is one of the most common causes of tree-related injuries and property damage. If you see dead branches in the canopy, especially over walkways or structures, professional pruning should be a priority.

Trees leaning more than before – A slight lean may be natural, but a new or increasing lean often signals root instability. Rutgers University explains that sudden leaning is a strong indicator of potential failure. Leaning trees near homes or driveways should be evaluated as soon as possible.

Cracks in the trunk or major limbs – Cracks weaken structural integrity and often worsen over time. The University of Maryland Extension identifies trunk cracks as a common warning sign of hazardous trees. These issues are easy to overlook but should never be ignored.

Fungal growth at the base of the tree – Mushrooms or shelf-like fungi near the trunk often indicate internal decay. The Missouri Botanical Garden explains that visible fungi usually appear after decay has already developed inside the tree. This is one of the most important signs to have evaluated by a professional.

Branches near power lines – Trees growing toward power lines create safety hazards and outage risks. The U.S. Department of Energy warns that tree contact is a leading cause of power disruptions. Never attempt to handle these situations yourself.