Original title: Giant trees have no trouble pumping water to top branches
Article
Researchers studying dipterocarp trees in Malaysian Borneo report that species up to 71 metres tall can maintain hydraulic function during drought at levels comparable to shorter trees. They measured vessel dimensions and leaf traits along whole trees and found taller trees compensate for height-related stress with wider base vessels and leaves that tolerate lower water potentials before wilting. The team compared trunk growth before, during and after the 2023–2024 El Niño drought and found no height-linked growth penalty in dipterocarps, challenging a common view that gravity and transport distance should make tall trees more vulnerable. The work argues that the tallest flowering trees, which hold over half of above-ground tropical forest carbon, may be less drought-sensitive than predicted by some climate-impact models. It is presented as a species- and site-specific result in a Science paper, and the authors call for broader testing across other very tall tree groups.
Commenters broadly welcome the finding but question how generalizable it is, citing a reported theoretical maximum that has excluded very tall claims and noting that no naturally occurring trees are known above roughly 130 metres. They point out that prior measurements often stop below that range and mention coastal fog uptake as an additional water source for some large trees, especially in fog-prone regions. Several commenters introduce the contested “structured water” hypothesis in xylem, offering recent supportive papers and older critiques to argue that alternative transport mechanisms remain unresolved in botany. Overall, discussion separates the paper’s robust dipterocarp-specific result from the broader claim that all giant trees are free from height-related hydraulic constraints.