Soot bamboo is bamboo that has been smoked in the smoke of farmers' hearths and kamado, and after 30 to 200 years of aging, it has turned an elegant candy color. It is popular as a color that evokes a sense of apology. It is called "hon soot bamboo" because it is the original sooty bamboo. It is now very valuable and is the highest quality material among bamboo materials.

The parts directly exposed to the smoke are darkly discolored, but the parts that are not directly exposed to the smoke, such as ropes wrapped around them, are lightly discolored.