Oak (bark) and other plants contain natural tannins and when these are used to make leather it is called vegetable dye. Any leather produced with a tannic acid bath made from vegetable matter, usually the bark of oak trees and water, is called veg dye leather. The skin, usually steer hide, is immersed in a series of baths over a period of several days. As the hide progresses from one bath to the next, the concentration of the tannic acid is reduced. Through these series of baths, which takes approx. seven days, the hide become a piece of leather.

Obvious characteristics of veg dye leather are its firmness, strength and lack of elasticity. Veg dye leathers are commonly used in western belts, saddles, harnesses, shoe soles and some luggages. Veg dye leathers are often marketed as carving leather, harness leather or sole leathers depending on the applications. Vegetable-dye leathers can be stretched especially when soaked in water and can also be carved, molded, hardened, dyed, painted, oiled, waxed.