Dynamic root-development models are indispensable for biomechanical and 
biomass allocation studies, and also play an important role in understanding 
slope stability. There are few root-development models in the literature, and 
there is a specific lack of dynamic models. Therefore, the aim of this study 
is to develop a 3D growth-development model for coarse roots, which is species 
independent, as long as annual rings are formed. In order to implement this 
model, the objectives are (I) to interpolate annual growth layers, and (II) to 
evaluate the interpolations and annual volume computations. The model 
developed is a combination of 3D laser scans and 2D tree-ring data. A FARO 
laser ScanArm is used to acquire the coarse-root structure. A MATLAB program 
then integrates the ring-width measurements into the 3D model. A weighted 
interpolation algorithm is used to compute cross sections at any point within 
the model to obtain growth layers. The algorithm considers both the root 
structure and the ring-width data. The model reconstructed ring profiles with 
a mean absolute error for mean ring chronologies of <9% and for single radii 
of <20%. The interpolation accuracy was dependent on the number of input 
sections and root curvature. Total volume computations deviated by 3.5?6.6% 
from the reference model. A new robust root-modelling tool was developed which 
allows for annual volume computations and sophisticated root-development 
analyses.