Non-destructive wood identification using X-ray µCT scanning: which resolution do we need?

Area of Science:

• Wood anatomy
• Paleoecology
• Cultural heritage studies
• Wood trade

Background:

• Traditional wood identification relies on anatomical features but often requires destructive sampling.
• X-ray computed micro-tomography (µCT) presents a non-destructive alternative for visualizing internal wood structures.
• A standardized resolution for wood identification using µCT is currently lacking.

Purpose of the Study:

• To compare the effectiveness of different X-ray µCT resolutions for wood identification.
• To determine the optimal resolution for distinguishing key anatomical features in African wood species.

Main Methods:

• 17 African wood species were scanned using X-ray µCT at four resolutions: 1 µm, 3 µm, 8 µm, and 15 µm.
• Scanned features were compared against established anatomical descriptions and images from the Inside Wood Online Database.
• The distinguishability and measurability of standardized anatomical features were assessed at each resolution.

Main Results:

• High resolutions (e.g., 1 µm) excel at visualizing small anatomical features like pits and fibers.
• Low resolutions offer a larger field of view, ideal for observing large-scale features such as vessel porosity and arrangement.
• An intermediate resolution of 3 µm proved optimal for recognizing a comprehensive range of anatomical features, facilitating wood identification.

Conclusions:

• X-ray µCT is a viable technique for non-destructive wood identification.
• All tested resolutions provide valuable anatomical information, with 3 µm offering the highest potential for identification.
• A publicly available dataset of scanned wood species is provided to promote the systematic use of µCT in wood identification.