Ash is definitively classified as a hardwood, a designation that is purely botanical and does not refer to the material’s physical density. The classification of wood as hard or soft is based on the type of tree from which it originates. Ash, like oak and maple, comes from a tree that is structurally different from those that produce softwoods such as pine or cedar.
Defining Wood Classification
The system that classifies wood separates all tree species into two main groups based on how they reproduce. Hardwoods are derived from angiosperms, which are flowering plants that produce seeds enclosed in a protective structure, such as a fruit or a shell. These trees are typically deciduous, shedding their leaves annually. Softwoods come from gymnosperms, which are non-flowering plants, usually conifers, that produce exposed or “naked” seeds, often in cones.
This botanical division means that a tree’s classification is entirely independent of the physical hardness of its lumber. For example, balsa wood is botanically a hardwood, yet it is one of the softest woods available. Conversely, some softwoods, like Douglas fir, can be harder than many woods classified as hardwoods. The terms provide a biological grouping for the source tree, not a direct measurement of the resulting wood’s durability.
Ash’s Botanical Status
Ash trees belong to the genus Fraxinus and are classified as angiosperms, placing them firmly in the hardwood category. As deciduous trees, they produce enclosed seeds and shed their leaves seasonally. This classification is further supported by the microscopic structure of the ash wood itself.
Hardwoods possess vessel elements, which are microscopic tube-like pores that transport water throughout the tree. Ash is characterized as a ring-porous wood, meaning its vessel elements are large and concentrated in the earlywood. These larger pores transition abruptly to much smaller pores in the latewood, creating the pronounced, open-grain pattern visible in the finished lumber. The presence and arrangement of these vessel elements confirm ash’s hardwood identity.
Practical Characteristics of Ash Wood
The unique structure of ash, particularly its ring-porous nature, contributes to its desirable material properties. Ash wood is known for its excellent combination of strength, elasticity, and shock resistance, which allows it to absorb impact without splintering. This quality is why ash has historically been a preferred material for tool handles, oars, and sporting equipment, most notably baseball bats.
White ash, a common variety, has an average Janka hardness rating of approximately 1,320 pounds-force (lbf), making it harder than species like black cherry and walnut. Despite this high practical hardness, ash has a straight grain and favorable workability, making it relatively easy to machine and turn. Its high density combined with an excellent strength-to-weight ratio makes it beneficial for projects like furniture and flooring where durability is required.