Shou Sugi Ban 焼杉板 (or Yakisugi) is the Japanese method of preserving wood through carbonization, a chemical reaction otherwise known as “fire” that seals the pores of the wood with carbon. This carbon is then often sealed into the wood using an oil-based sealant.
Traditionally Shou Sugi Ban is used to prepare boards for use as exterior siding on buildings though in the last few years the finishing process has gained popularity as a treatment for interior wood used in furniture and wall facades.
The traditional method often has the craftsman binding two or three long Japanese cedar (Sugi) planks together with a fire lit between the boards. The boards are then stood upright to form a chimney along which the fire progresses until the boards have been evenly charred. More modern methods may replace process this with scorching via a common handheld gas torch. At this point the boards are quenched with water and scrubbed with a stiff bristled brush or broom to removed loose soot and carbon material and left to dry. Finally the planks are sealed with an oil leaving a gorgeous shimmering coal-like appearance.
The benefits of the finish go beyond aesthetics as Shou Sugi Ban offers increased fire resistance, reduces susceptibility to rot, and protects the wood from damaging attacks by insects.
Beetle Kill Pine or Denim Pine is a variety of white pine that has been attacked by beetles. These beetles carry a certain kind of mold on their bodies that then infiltrates the sugary wood and spreads quickly, affecting everything except for the heartwood at the core of the tree. This mold stains the wood a beautiful blue hue creating a very interesting effect.
In the late 1990s and early 2000s, extended drought triggered the infestation of nearly 1.5 million acres of forest in Colorado and southern Wyoming, though the infestation occurs all over. The problem affected such a large portion of the Colorado wilderness that the dead and dying trees have become a danger and efforts to remove the trees have proved to be problematic. Unfortunately the demand for Beetle Kill Pine is low as the lodgepole pine that is usually infected is a softwood, often of small diameter, and also susceptible to many other diseases as well.
Beetle Kill Pine is not news. In fact Core77 wrote a series of articles on it back in 2012. I am writing about it now because I recently purchased a a large slab for an upcoming project from Hobby Hardwood and thought the history about the beautiful material is pretty interesting. In fact one of the workbenches I use in the shop is made of boards hand selected for their coloration when I originally built the table to be used as a pub-height dining table.