TLS data acquisition was carried out with a Trimble TX5 3D phase-shift laser scanner (Trimble Navigation Limited, USA) operating at a 1550 nm wavelength and measuring 976,000 points per second, delivering a hemispherical (300° vertical x 360° horizontal) point cloud with an angular resolution of 0.009° in both vertical and horizontal direction with a maximum range of 120 m (resulting a point distance approximately 6.3 mm at 10-m distance) and beam divergence of 0.011°. All three study sites were scanned between September and October 2018 using a multi-scan approach to minimize occlusion. Eight scans were conducted at each sample plot with two scans on two sides of a plot center and six auxiliary scans closer to the plot borders (see Figure 1 in Saarinen et al. 2020). Artificial targets (i.e. white spheres with a diameter of 198 mm) were placed around each sample plot to be used as reference objects for registering the eight scans into a single, aligned coordinate system with a FARO Scene software (version 2018). The registration resulted in a mean distance error of 2.9±1.2 mm, mean horizontal error was 1.3±0.4 mm, and mean vertical error 2.3±1.2 mm. LAStools software (Isenburg 2019) was used to remove topography from the point clouds by applying a point cloud normalization workflow presented by Ritter et al. (2017).