Casla mainly grows in Myanmar, Laos, Africa and other regions, belonging to high-grade wood, with yellow-red or dark brown color, holes like pineapple and black walnut, and stable wood.

Beech is also written as "ash wood" or "ash wood". Produced in the south of China, the north doesn't know this name, but this wood is called Nanyu. Although it is not luxurious wood, it is widely used in traditional furniture in Ming and Qing dynasties, especially among the people. This kind of beech furniture is mostly Ming-style, and its shape and manufacturing technology are basically the same as those of hardwood furniture such as Huang Huali, which has considerable artistic and historical value. Beech wood is heavy, strong, impact resistant, easy to bend under steam, can be made into various shapes, and has good nail holding performance. It is unique to Jiangnan, with clear texture, uniform texture and soft and smooth timbre. It is heavier than most ordinary hardwoods and belongs to the upper-middle level in all wood hardness rankings.