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Differences (mean ± SE) between trees and grasses in (a) whole‐plant water‐use efficiency (WUE) and (b) relative growth rate (RGR). Statistically significant differences between tree and grass leaf osmotic potential (Ψosm) were determined via linear mixed effects model (*, P < 0.05).

Differences (mean ± SE) between trees and grasses in (a) whole‐plant water‐use efficiency (WUE) and (b) relative growth rate (RGR). Statistically significant differences between tree and grass leaf osmotic potential (Ψosm) were determined via linear mixed effects model (*, P < 0.05).

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Models of tree–grass coexistence in savannas make different assumptions about the relative performance of trees and grasses under wet vs dry conditions. We quantified transpiration and drought tolerance traits in 26 tree and 19 grass species from the African savanna biome across a gradient of soil water potentials to test for a trade‐off between wa...

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