Unique type of bamboo distinguished by its rich, dark amber-brown appearance, developed over time through exposure to soot. This soot, from the irori, a traditional hearth located in the center of rural Japanese homes, rises through the building and settles beneath the roof. The bamboo stalks used as structural elements in traditional thatch roofs need to absorb this soot over a period of more than 150 years to achieve their distinctive dark color.

Once straighten and cleaned, the patina gained over the years reveals its beautiful amber-brown hues. The lighter spots visible show where ropes were wrapped around the bamboo to mount it; with less exposure, these areas retained a lighter hue. The soot not only enhances the bamboo’s aesthetic appeal but also serves as a natural barrier against insects and decay.