Fig. 4From: Modelling of root reinforcement and erosion control by ‘Veronese’ poplar on pastoral hill country in New ZealandRoot distribution data fitted using the PN dataset (Douglas et al. 2010), considering four tree densities: 89, 160, 210, and 237 sph (corresponding to mean stem distances (D) of 10, 8, 7, and 6.5 m, respectively). Points correspond to the data of the mapped trenches (P), the continuous line shows the results of the calibrated model, and the dashed lines the 95 % confidence interval. T indicates the position of the trees in the transectBack to article page