Ash and oak are closely related in appearance. In fact, ash is often used as a substitute for oak since it is usually priced 20 to 25 per cent lower per board foot. The two hardwoods come from different tree families and, while they share many properties, there are a few differences that could make one a better choice over the other depending on how the wood will be used.
About 17 different species of ash grow in the Eastern United States and Canada. Only two of them—white ash (Fraxinus Americana) and black ash (Fraxinus Nigra)—are viable as commercial products. Trees can reach 80 to 120 feet in height and 2 to 5 feet in diameter. Ash is part of the olive family even though its wood is unscented.
Oak has a similar growing range to ash, but oaks are found further west, along an Oklahoma to Minnesota line, further south, into Georgia, and further north, into Ontario. Oak is by far the most abundant hardwood species in North America, supplying about 37 per cent of the total board feet of hardwood available. A member of the beech family, oaks can reach 80 feet in height. These trees produce acorns, a vital food source for deer, squirrels and wild turkeys.
The grain of ash and oak is porous and coarse, somewhat more so in oak than in ash. Ash wood fibres are long, which tends to make it splinter when worked. However, these long fibres also give the wood strength in a finished project.
Both ash and oak are characterised by wide, sweeping bands of darker grain that contrast with the rest of the wood. Ash is light in colour, varying from white to a creamy yellow. Unstained, white ash can develop a yellow patina, but black ash tends to keep its natural uniform tan to brown colour. Red oak, the more popular oak hardwood, is reddish in colour to white oak's nearly greenish tint. All types of oak and ash take stains well.
Ash is lighter and less dense than oak, but it still has great strength. It is used to make hockey sticks, baseball bats and handles for tools. The wood absorbs shock, which is why it is favoured for use as bats. Ash is also used for furniture, kitchen cabinets, flooring, millwork and chairs and stools. Oak is also used to make furniture pieces and cabinetry, flooring and millwork. It is used to make barrels and sleepers. Oak has great crush resistance.
Both woods machine equally well and hold together with glue and fasteners. Pre-drilling is recommended for nails and screws. Both ash and oak have good steam bending characteristics. Oak wood has tannins present, which help the wood resist fungus and insect attacks.