3.2. Results of Segmented Regression Analysis

First, a segmented regression was applied to all the data sets of pruning severity and diameter growth response. The results are depicted in Figure 1. A breakpoint was found at 25% crown removed and almost significantly supported by score test (p = 0.07). The first segmented line (β = -0.25, 0 < severity < 25) was not significant (p = 0.57).