Which of the following observations might indicate a tree is at risk?

Unexplained leaf drop during a season when other trees are healthy is a significant warning sign that a tree may be at risk. This phenomenon can indicate underlying stress factors affecting the tree, such as limited water availability, nutrient deficiencies, diseases, or pest infestations. When a tree drops leaves while others remain healthy, it suggests that it is not thriving and possibly struggling to meet its physiological needs. Monitoring and analyzing such symptoms can aid in identifying potential issues and mitigating risks before they lead to significant damage or tree failure.

In contrast, uniform branch density, consistent growth in height, and regular flowering are typically indicators of a healthy tree. A uniform branch structure suggests balance and stability, growth in height indicates the tree is thriving, and regular flowering is a sign of good vitality and reproductive success. Therefore, these characteristics do not raise immediate concerns about tree risk.