ISA Certified Arborist Practice Exam 2025 – All-in-One Resource for Comprehensive Exam Success!

Pruning wound closure refers to the healing process that occurs after a branch is removed from a tree. This biological process involves the tree developing callus tissue to cover and protect the exposed area where the cut was made. The tree utilizes its natural defense mechanisms to seal the wound and prevent pathogen invasion, which is crucial for maintaining overall tree health.

During this process, the tree's growth cells proliferate at the edges of the cut to form a protective barrier. This healing response is vital because it helps reduce the risk of decay organisms entering the tree, which can result in further stress or disease. Proper pruning techniques that minimize the size of the cut can enhance the effectiveness of this wound closure process, allowing trees to recover more quickly and maintain structural integrity.

Understanding this healing process is important for arborists as they aim to make cuts that promote health and longevity in the trees they manage. The other options, while related to aspects of pruning care, do not accurately capture the primary focus of pruning wound closure.