Also read kōzogami and kajigami 梶紙. Formerly called kokushi 穀紙 during the Heian period. Paper made from the fibers of the mulberry tree, kōzo 楮 (broussonetia kajinoki 梶の木), which is native to Japan and widely cultivated. Considered the standard variety of Japanese handmade paper, it has been used since ancient times. The mulberry fibers are long (5-20 mm) and easy to handle, thus creating a fine, strong paper.
About half of Japan's mulberry is grown in Kōchi Prefecture. The rest comes from Ibaraki, Shimane, Nagano, and Fukuoka Prefectures. The type of mulberry used varies from region to region, and therefore, the color and quality of the paper differs widely. Varieties of choshi include: *danshi 檀紙; *suiharagami 杉原紙; *hōsho 奉書; and *tengujō 典具帖. Choshi has been used for official documents, poetry, sliding screens *shōji 障子 and *fusuma 襖, lanterns, umbrellas, fans, and so on.
Choshi reached its peak in terms of quantity of production and variety of uses in the late Edo period. However, with the introduction of western paper and machine production, the output of choshi declined dramatically. Nevertheless, it is still very popular in folk crafts such as dollmaking and is used by artists for calligraphy, printmaking, traditional Japanese style painting, and as mounting paper.