Laser scanning may help prevent urban trees from falling

Scientists at the University of São Paulo have employed LiDAR technology to assess tree health and improve pruning techniques to minimize the risk of trees falling over, particularly in urban environments. LiDAR, or light detection and ranging, generates a 3D digital mold known as a point cloud, which precisely mirrors a plant's structure using millions of coordinates.

By simulating wind strength and identifying regions of mechanical vulnerability, the technology calculates which branches should be trimmed to distribute stress and enhance the tree's overall resilience. The goal is to develop an app that utilizes LiDAR and other techniques to make trees less susceptible to wind, thereby reducing the risk of falling trees.

In December 2025, strong winds in São Paulo and surrounding areas caused 1,327 reported incidents of fallen trees, resulting in injuries and power outages affecting over 2 million residents. Improper pruning exacerbates the issue, especially in wind tunnels, urban canyons, and during the rainy season when wind, rain, and temperature fluctuations increase the likelihood of tree failure, particularly in poorly managed or diseased trees.

The study, published in the journal Trees: Structure and Function, involved scanning a rosewood tree commonly found in urban landscaping. The scan captured 30 million points, which were then processed to simulate wind and optimize pruning based on topological optimization. While the pruning algorithm recommends removing no more than 20% of the tree's total mass to maintain structural integrity, human labor remains essential for pruning tasks.