Yakisugi. Ancient Japanese technique for making wood more sustainable.
Preserving wood by burning its surface is an ancient Japanese technique called yakisugi. In the western world it is also known by the brand name "shou sugi ban". Back in the day, Dutch farmers and landowners would use this technique to extend the service life of fence poles by burning them before placing them in the soil.
This technique was revived when the Japanese architect Terunobu Fujimori incorporated it into his designs at the end of the last century.