Species spotlight: white oak.
In this issue's Species Spotlight, Timber Products veneer expert Eric Cullen shares his insight on White Oak and the differences between true rift and false rift.
White Oak (Quercus spp.) is a domestic species found in the eastern parts of the United States and Canada. Its heartwood is light to dark brown, sometimes with hints of pink or yellow. Heavy, hard and strong, White Oak features straight grains with a coarse texture.
White Oak is currently popular in a variety of market segments, including residential cabinets, store fixtures and hospitality. Its closed-cell structure makes it water- and rot-resistant, which is why it is used for wine and whiskey barrels.
White Oak is available in rotary cut, plain sliced, quartered, rift and false rift. Rift and false rift are currently very popular. Quarter sliced intentionally produces straight grain while maximizing the amount of medullary ray "flake" seen. Rift-cut intentionally produces straight grain, while minimizing the amount of medullary ray "flake" seen.
True or False Rift?
White Oak is the most prevalent species for false rift. False rift is straight grain that is unintentionally produced when a log is flat sliced. It may be because a defect was clipped out, causing the cathedral to not be used, or when the knife reaches the back of the cant where it is cutting close to a right angle across the growth rings. False rift can sometimes be difficult, if not impossible, to distinguish from true rift, although when large samples of faces are viewed, there are differences that become apparent. If you are paneling a large expanse, such as a courtroom, true rift would be preferable.
The more obvious differences between true and false rift are that more slope, swing, flake and narrow components are seen in false rift. Faces with more slope and sweep develop the appearance of a manufactured cathedral when book-matched. The narrow components cause fewer sheets to be produced from a single flitch, leading to fewer and smaller sequences.
True rift is more desirable because it is more consistent for straight grain. It has less slope, sweep and flake. False rift is similar in appearance but less expensive and currently is in great demand in the market.