White oak and red oak look alike across a showroom, but the USDA Forest Products Laboratory separates them by their pores.
The wood properties below come from the Laboratory’s Wood Handbook.
How the Forest Products Laboratory Tells Them Apart
- White oak group: The heartwood pores are usually plugged with growths called tyloses. The Handbook says this makes the wood impenetrable to liquids, so most white oaks suit tight cooperage. The heartwood is generally grayish brown. The wood is somewhat heavier than red oak, and the heartwood has good decay resistance.
- Red oak group: The pores generally lack tyloses and stay open. The Handbook calls red oak unsuitable for tight cooperage unless the barrels are lined with sealer or plastic. The heartwood is brown with a tinge of red. The Handbook says red oaks have fairly high shrinkage upon drying.
- Both groups: The sapwood is nearly white and roughly 1 to 2 inches wide. Quartersawn lumber shows broad, conspicuous rays. The Handbook lists furniture among the uses of both groups.
The Handbook says red oak lumber cannot be sorted by species on wood characteristics alone. It can be separated from white oak by the size and arrangement of pores in latewood and by the lack of tyloses.
Shrinkage Numbers
Table 4-3 of the Wood Handbook gives shrinkage from green to ovendry, as a percent of the green dimension.
- White oak: 5.6 percent radial, 10.5 percent tangential, 16.3 percent volumetric.
- Northern red oak: 4.0 percent radial, 8.6 percent tangential, 13.7 percent volumetric.
- Southern red oak: 4.7 percent radial, 11.3 percent tangential, 16.1 percent volumetric.
These are totals for fully dried wood. A finished table moves only a fraction of that between a dry room and a humid one. See Solid Wood Movement in Tabletops for a worked estimate.
Oak in Arkansas Timber
The Encyclopedia of Arkansas says the Beirne mill of Anthony Timberlands in Clark County produces hardwood lumber, primarily oak. The timber comes from the bottomlands of the Ouachita, Saline and Little rivers. The Encyclopedia does not say which oak group the mill saws. Read more in Saline River Bottomland Hardwoods.
The Wood Handbook lists southern red oak among the principal red oaks. It lists overcup oak and swamp chestnut oak in the white oak group.
What the Shop Lists
Saline River Workshop’s listings show how oak appears in a catalog. Two titles name white oak: the Solid White Oak Coffee Table and the Solid White Oak High Table and Chair Set.
Three titles say only oak: the Rustic Oak Console Table, the Exceptional Oak Table and the Solid Oak High Table and Chair Set with mortise and tenon construction.
Ask which group a listing uses when the title says only oak. The contact page lists a workshop in Wilmar, Arkansas.
Questions to Ask Before Ordering
- Species group: Ask whether the top is white oak or red oak.
- Cut: Ask whether boards are plain sawn or quartersawn. The Handbook says quartersawn oak shows broad rays.
- Source: Ask where the mill sawed the lumber.
- Drying: Ask what moisture content the boards reached before the build began.
Saline River Workshop builds in southeast Arkansas. For a first look at Bradley County timber, read Warren, Arkansas Hardwood and Custom Furniture.
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