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Zhao (1) considers our examination (2) of the relationship between deuterium offset (hereafter “Δ”) and stem gravimetric water content (hereafter “W”) across all the study species to be misleading, and instead suggest that data should be analyzed by individual habitat type based on a vague argument that “different habitats/species will behave differently.” Such a suggestion is unjustified as it ignores the fact that the results of our experiment have already ruled out root uptake-related fractionation (which, if present, would justify the use of a habitat type-based approach) as a mechanism underpinning Δ. As a matter of fact, given our demonstration that extractionassociated deuterium depletion is an unavoidable consequence of plant stem dry matter comprising a high fraction of exchangeable organic hydrogen (3, 4)—unless there is evidence for a role of habitat type in influencing this “fraction”—we have no reason to …