A terrestrial laser scanning (TLS) experiment was carried out in the EAGLE 2006 campaign to characterize and model
the canopy structure of the Speulderbos forest. Semi-variogram analysis was used to describe spatial variability of the
surface. The dependence of the spatial variability on the applied grid size showed, that in this forest spatial details of the
digital surface model are lost in the case of larger than 0.3-0.4 m grid size. Voxel statistics was used for describing the
density of the canopy structure. Five zones of the canopy were identified according to their density distribution. Basic
geometric structures were tested for modeling the forest at the individual tree level. The results create a firm basis for
modeling physical processes in the canopy