Hardwood Floors August/September 2019

SPECIES SPECS Re d Oa k RESOURCES

Quercus rubra

distinguish red oak from white oak. Red oak will only produce a slight brown discoloration, whereas white oak will turn dark brown to black. GRAIN: • The grain is straight, open, and medium to coarse, with an uneven texture. Less pronounced figure than white oak with smaller rays. • Quartersawn red oak can have a ray flake pattern, sometimes referred to as tiger rays or butterflies. • Depending on the origin of the tree and variation in growing seasons, northern-grown red oaks tend to have a tighter, more uniform grain pattern than southern- grown red oaks. HARDNESS (JANKA): DIMENSIONAL STABILITY: AVERAGE • Northern red oak has a dimensional stability factor of 4.0 percent (radial) and 8.6 percent (tangential), meaning this species may shrink/swell up to 8.6 percent of its given width, depending on how it’s cut, when going from green (30 percent MC) to oven dried. • Southern red oak has a dimensional stability factor of 4.7 percent (radial) and 11.3 percent (tangential), meaning this species may shrink/swell up to 11.3 percent of its given width, depending on how it’s cut when going from green (30 percent MC) to oven dried. • Northern red oak averages 1290. • Southern red oak averages 1060.

ORIGIN: The Quercus rubra genus (red oak) group contains several species of oak that share many similar characteristics. This group includes subspecies such as pin oak (Q. palustris), black oak (Q. velutina), northern red (Q. rubra), southern red (Q. falcata), cherrybark (Q. falcatavar), scarlet oak (Q. coccinea), laurel oak (Q. laurifolia), willow oak (Q. phellos), and others. Red oak trees typically grow throughout much of Eastern Canada and the U.S., but are also grown in the UK, Europe, and Iran. USES: Commonly used in flooring, furniture, millwork, cabinetry, and for decorative veneers. COLOR: Heartwood is light biscuit to medium brown with a reddish to pinkish cast. White to light brown sapwood isn’t always sharply demarcated from the heartwood. Red oak can have a broad range in color variation. DIFFERENTIATING WHITE OAK FROM RED OAK: • Other than color, there are a couple other ways to differentiate between red oak and white oak: - When viewing the end grain, the large earlywood pores found in red oak are open and empty. The pores of white oaks are plugged with a bubble-like structure called tyloses. This tyloses is why white oak works so well as wine and whiskey barrels. - Sodium nitrite (NaNo2) as a reagent in a 10 percent solution of water, when applied to oak, will quickly

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