Canaigre
Canaigre, a large plant related to the common sorrel. It is found mainly in the southwestern United States and northern Mexico. Its dried tubers are an excellent source of tannin, a substance used in the tanning of leather. The plant grows one to three feet (30 to 90 cm) high.
Canaigre is Rumex hymenosepalus of the buckwheat family, Polygonaceae.