Vegetation structure
In order to assess the effects of livestock on vegetation structure we
performed two Principal Component Analyses (PCA). Both PCAs were based
on standardized correlation matrix with the function PCA (package
‘FactoMineR’ (Lê et al., 2008)). The first PCA was performed using the
data from all study trees (N = 72) to assess the differences among the
three categories of trees (control, one-year exclusion and ten-years
exclusion). In the second PCA, we only included control oaks (N = 24) to
analyse the differences among the three oak savannas with free-range
livestock excluding the effect of the experimental treatment. PCA tables
can be found in Table S7.