“…Trees respond to reduced water supply by modifying their belowground C allocation (Ruehr et al ., 2009; Hagedorn et al ., 2016; Hommel et al ., 2016) and potentially increase root exudation rates (Karst et al ., 2017; Karlowsky et al ., 2018; Preece et al ., 2018; de Vries et al ., 2019; Jakoby et al ., 2020). However, most studies only use single root branches – defined as ephemeral terminal branch orders – to describe a plant's exudation behavior, which does not consider changes in root growth, distribution, and longevity that can also be significantly altered under drought (Nikolova et al ., 2020; Zwetsloot & Bauerle, 2021). Allometric scaling of root exudates from a single root branch to the entire root system, while accounting for changes in root production and longevity, can advance our understanding of species‐specific belowground C allocation patterns during periods of drought and improve terrestrial biosphere models (Fatichi et al ., 2019).…”