In City of Chico v. Superior Court (McKenzie), published August 30, 2021, the Third District Court of Appeal issued a writ directing a trial court to grant the petitioner city summary judgment. While jogging on a bike path in a municipal park, the plaintiff was injured by a falling tree branch. She sued the city for maintaining a dangerous condition of public property. The park is a naturally occurring riparian woodland. The tree is a 160-year-old Valley Oak Tree. It predates the park. Valley oaks are indigenous to the park location. Valley Oaks are subject to sudden branch drop, which cannot be anticipated; it is often associated with long, horizontal branches and warm temperatures. The city moved for summary judgment based on Government Code section 831.2's immunity from liability for injuries caused by a natural condition of unimproved public property. The plaintiffs submitted expert evidence that the tree had been pruned, and that pruning can push growth into the remaining branches, increasing their diameter. They did not submit evidence that previous pruning actually caused the branch to break. The trial court denied summary judgment, finding triable issues of fact on whether the injuries were caused by a natural condition of unimproved public property.
The appellate court ruled that the city was entitled to section 831.2 immunity as a matter of law. The natural growth of indigenous trees in natural habitats is a natural condition. Pruning did not change that. Natural condition immunity is not lost because of changes that duplicate models common to nature combine with natural forces to shape the condition. Despite the pruning, the continued growth of the tree was a natural condition. The tree grew on unimproved property; that the branch fell on (and the injury occurred on) an improved path did not change that the condition was on unimproved public property. There was no evidence that the pruning caused the branch to fall; at most there was evidence it affected the diameter of the branches, which did not cause branches to drop.