Density is a crucial variable in forest and wood science, but gravimetric methods of measurement are mostly destructive and time-consuming. De Ridder et al. derive profiles of wood density variations for the African species Terminalia superba with a resolution of approx. 50 µm from resistance drillings, neutron and X-ray scans. They find that high-resolution X-ray-computed tomography is a very promising technique for microdensitometry of wood cores.