The long-term durability of wood, especially in an outside area, requires a proper preservation treatment. Among the various modern wood modification techniques, (acetylation, furfurylation,  silicification), thermal treatment at 180-250 °C in low-oxygen conditions, known as thermally modified timber (TMT), is likely the least environmentally problematic option. However, TMT is compromised by reduced structural integrity due to the thermal degradation of its components. An alternative that provides adequate protection for wood surface while maintaining its interior mechanical properties is surface charring. This technique, traditionally employed in Japan (yakisugi), or in Europe (preserving vineyard posts buried in soil),  has recently been enhanced by a hot plate method  [1]. Our  contribution will present some further innovative techniques for carrying out selective radiofrequency and/or microwave charring of wood surfaces. The primary advantage of utilizing electromagnetic radiation for wood charring lies in the enhanced control over heat distribution across larger areas of treated timber. A thin pyrolytic layer was formed on the wood surface through methods such as a specially designed kHz frequency non-thermal arc discharge, open flame, hot furnace, and conductive spray (for the refference). The objective was to develop a high-quality absorber (susceptor) for incoming electromagnetic radiation. The characteristics of the produced films are compared in terms of microscopic structure, mechanical properties (hardness), and electromagnetic heating efficiency. While wood preservation is the central theme of our research, from a broader perspective, biomorphic porous structures derived from renewable natural materials like wood hold significant potential for applications in areas such as catalysis, gas separation/storage, and electrode components. Pyrolytic conversion serves as the initial step in creating many of these biomorphic templates. Therefore, the insights gained from our study can also be applied to the production of larger biomorphic templates. Acknowledgment: This research has been supported by the Czech Science Foundation (GAČR), project No. 24-10430S.