Baragur Neelappa Divakara*, Chitradurga Umesh Nikitha, Anil Kumar Sethy
Institute of Wood Science and Technology, Indian Council of Forestry Research and Education (ICFRE), Bengaluru 560003, India.
*Corresponding author:Baragur Neelappa Divakara
Abstract
This study investigates the effectiveness of Electric Resistance Tomograph (ERT) as a non-invasive, accurate, and cost-effective method compared to traditional destructive methods for distinguishing between heartwood and sapwood in Tectona grandis L.f. (teak), a species valued for its durable timber. ERT is a sophisticated diagnostic tool that produces high-resolution tomographic images by capturing differences in electrical resistivity, which are influenced by variations in moisture content and conductivity within the wood. Teak discs were analysed by placing sensors at uniform intervals around their circumference and connecting them to an ERT multi-cable system. The resulting tomograms were then compared with manually recorded sap-wood-heartwood (SW-HW) boundaries. The ERT images displayed a distinct resistiv-ity gradient, with lower resistivity values indicating sapwood (blue zones) and higher values corresponding to heartwood (red zones). A strong linear correlation (R² = 0.93) between ERT-derived and manually measured heartwood areas confirmed the method's accuracy. The study further discusses how environmental conditions may affect resistivity readings and suggests improvements for ERT calibration to enhance its field applicability. These findings demonstrate the potential of ERT as a reliable, non-destructive technique for assessing internal wood structure and quality in teak, with promising applications in forest management, timber grading, and tree breeding programs for other heartwood-producing species.
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How to cite this paper
Differentiating Heartwood and Sapwood in Tectona grandis Linn.f. (Teak) Using the Electric Resistance Tomograph (ERT)
How to cite this paper: Baragur Neelappa Divakara, Chitradurga Umesh Nikitha, Anil Kumar Sethy. (2025). Differentiating Heartwood and Sapwood in Tectona grandis Linn.f. (Teak) Using the Electric Resistance Tomograph (ERT). Advance in Sustainability, 5(1), 40-49.
DOI: http://dx.doi.org/10.26855/as.2025.06.005