wisteria ash
Ash made from wisteria vines, traditionally used in the Japanese tea ceremony to prepare the hearth.
茶道では、炉に藤灰をまいて炭を置く。
In the tea ceremony, wisteria ash is spread in the hearth before placing the charcoal.
Compound of 藤 (fuji, 'wisteria') and 灰 (hai, 'ash'), referring to ash produced from wisteria vines.