Data from: Shoot growth of woody trees and shrubs is predicted by maximum plant height and associated traits

1. The rate of elongation and thickening of individual branches (shoots)
varies across plant species. This variation is important for the outcome
of competition and other plant-plant interactions. Here we compared rates
of shoot growth across 44 species from tropical, warm temperate, and cool
temperate forests of eastern Australia. 2. Shoot growth rate was found to
correlate with a suite of traits including the potential height of the
species, xylem-specific conductivity, leaf size, leaf area per xylem
cross-section, twig diameter (at 40 cm length), wood density and modulus
of elasticity. 3. Within this suite of traits, maximum plant height was
the clearest correlate of growth rates, explaining 50 to 67% of the
variation in growth overall (p < 0.0001), and 23 to 32% of the
variation (p < 0.05) in growth when holding the influence of the
other traits constant. Structural equation models suggest that traits
associated with ‘hydraulics’, ‘biomechanics’, and the ‘leaf economics
spectrum’ represent three clearly separated axes of variation, with the
hydraulic axis exhibiting the strongest alignment with height and largest
independent contribution to growth (in the case of branch thickening).
However most of the capacity of these axes to predict growth was also
associated with maximum height, presumably reflecting coordinated
selection on multiple traits that together influence life histories. 4.
Growth rates were not strongly correlated with leaf nitrogen or leaf mass
per unit leaf area. 5. Correlations between growth and maximum height
arose both across latitude (47%, p < 0.0001) and from within-site
differences between species (30%, p < 0.0001). Covariation between
growth and maximum height was driven in part by variation in irradiance
across sites as well as among canopy positions within sites (23%, p
< 0.0001). A significant fraction of this shared variation was
independent of irradiance (45%, p < 0.0001), reflecting intrinsic
differences across species and sites.