Study
The limits to tree height
Koch, George W.; Sillett, Stephen C.; Jennings, Gregory M.; Davis, Stephen D.
Nature, 2004
Researchers climbed five of the tallest known coast redwoods and sampled leaves and measured water potential at intervals from the base to the top, testing whether water transport or something else sets the ceiling on height.
- Studied in
- Sequoia sempervirens
- Sample size
- 5 coast redwoods over 110 m, climbed and sampled at intervals up the trunk
Leaf water potential became steadily more negative with height, and photosynthesis fell, as the pull needed to lift water against gravity and friction approached the limit at which the water column cavitates. Extrapolation put the maximum achievable height at roughly 122–130 m.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Tree height is limited by the hydraulics of lifting water, which progressively restricts leaf expansion and photosynthesis near the top.
How NatureHQ reads it
The elegance is in the method: the only way to answer "why do trees stop growing" was to climb the tallest ones and measure the top. A tree has no pump — water is pulled up by evaporation at the leaves, held together by the cohesion of water itself under enormous tension — and at some height that column simply cannot be sustained. The predicted ceiling sits just above the tallest tree ever measured, which is the kind of agreement that makes a hydraulic explanation hard to argue with.
- One species, at the extreme of its range; other tall species may hit different limits first.
- Five individuals, necessarily — there are not many 110-metre trees.
- Mechanical and nutrient limits may also operate and are not separated here.
Climbing the tallest trees to find out why they stopped
Why do trees stop getting taller, and what sets the ceiling?
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: Nature PortfolioPublished in a Nature Portfolio journal.
This reference was resolved automatically against Crossref on 2026-08-11.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-08-10.