The term 'TREE TIMBER' can be broken down into three crossword solutions: ASH (3 letters), SAL (3 letters), and KOA (3 letters). ASH is a type of tree that is native to Europe, North Africa, and parts of Asia. It is a deciduous tree that is known for its hardwood and is often used for furniture and flooring. Sal is a type of tree native to India and Southeast Asia. It is a hardwood tree that is often used for construction and furniture. Koa is a type of tree native to Hawaii. It is a hardwood tree that is often used for furniture and musical instruments. All three types of trees are used for timber, which is wood that is cut into logs or other shapes for use in construction and other purposes.