Table 1.

The rationale of the study

Question	Methodology and analysis	Expected results	Figures
How does the state of stress of bark change with ontogeny?	Regression between bark residual strain and stem diameter.	Tensile stress increases in species relying on bark for postural control.	Fig. 5; Supplementary Table S2
Do species that differ in their bark mechanical behavior present different bark allometries?	Allometric analysis (standard major axis regression) between bark thickness and stem radius and wood thickness.	Species with tensile stress produce more bark (i.e. higher allometric exponent) than species with compressive stress.	Figs 2, 3; Supplementary Fig. S1; Table 4
Does bark density vary with ontogeny? Are bark density changes related to changes in the state of stress of bark?	Regression between bark density and stem size.	As both high bark density and compressive stress are associated with high level of bark sclerification (Lehnebach, 2019), tensile stress is associated with low bark density.	Fig. 4

Each question is described with the associated methodology, analysis, and expected results. The table also refers the reader to the figures and tables that give the the actual results associated with each question.