Harvey Brown

Trees quietly draw water from their roots to their highest leaves, lifting it over 100 meters without any visible mechanism. Most of this water evaporates, and only a small amount is used for photosynthesis. For centuries, this process puzzled scientists until the late 19th century, when the Cohesion-Tension (CT) theory explained how evaporation and water molecule cohesion make this possible. Despite this breakthrough, researchers still debate the details: how water moves through roots and nanoscale spaces, how trees survive cavitation and repair themselves, and how climate change could disrupt this balance. Professor Harvey Brown examines these ongoing mysteries in this article.