Study
Comment on "The global tree restoration potential"
Veldman, J. W.; Aleman, J. C.; Alvarado, S. T.; Anderson, T. M.; Archibald, S.; Bond, W. J.; Boutton, T. W.; Buchmann, N.; Buisson, E.; Canadell, J. G.
Science, 2019
A formal technical comment re-examining the restoration map and carbon accounting of an earlier paper, focusing on which biomes were classified as suitable for additional tree cover.
A large share of the mapped "restoration" area was ancient grassland, savanna and open woodland, which are not degraded forest and hold much of their carbon below ground. The comment argues the carbon benefit was substantially overstated and that planting trees in these systems would damage them.
What it means
The authors' reading, and ours. Where they differ, that difference is the point.
How the authors put it
Naturally open ecosystems are not deforested land, and treating them as restoration targets overstates the carbon available and threatens biodiversity.
How NatureHQ reads it
The correction that makes the original citable. Read together the pair say something more useful than either alone: tree cover can be increased in many places, the carbon benefit is far smaller than the headline, and the map of where it is possible is not a map of where it is a good idea. NatureHQ carries both records so a reader who arrives with the famous figure meets the argument about it rather than a flat contradiction.
- A commentary rather than new field measurement.
- Disputes the interpretation and the accounting rather than producing an alternative global estimate.
What this study is used for on NatureHQ
One study can inform several subjects. Here is everywhere this one is cited.
Published by: American Association for the Advancement of SciencePublished in Science or Science Advances (AAAS).
doi.org/10.1126/science.aay8060
This reference was resolved automatically against Crossref and OpenAlex on 2026-08-30.
NatureHQ summarises research in its own words and does not reproduce published text. Reviewed 2026-08-30.