A long, rough fibre from the mulberry tree that produces strong, absorbent sheets of paper. Kozo is the most common fibre used in Japanese papermaking.

Broussonetia spp, several species of the paper mulberry used in papermaking, the fibres are long and sinewy.

The most widely used bast fiber used in Japanese paper making. Commonly known as "paper mulberry."

Traditional Japanese paper made of mulberry fiber used in woodblock prints.