Reference Surface vs. Reconstructed Surface
Comparing the plots where we collected imagery after destructive harvesting and reconstructed the ‘true’ reference ground surface using SfM (n = 35) with our reconstructed interpolated ground surface showed a decrease in R2 from 0.44 to 0.42 at 5 mm voxels (Fig. 5). The mean absolute difference in volumes was 20% of the volume calculated using the reference ground surface.