Variations within species and grades: Considerable variation among boards in color and grain texture, but variations not as pronounced as in red oak.
Hardness (Janka): 1360; 5% harder than Northern red oak.
Dimensional Stability: Average (change coefficient .00365; 1% more stable than red oak).
Durability: More durable than red oak. Tannic acid in the wood protects it from fungi and insects.
Sawing/Machining: Excellent machining qualities.
Sanding: Sands satisfactorily.
Nailing: Good resistance to splitting; excellent holding ability.
Finishing: Absorbs finishes more evenly than red oak. Does not bleach well.
Comments: During the finishing process, tannins at the surface can react with some liquids to turn the wood green or brown. This effect tends to be more pronounced with products that have a high water content, such as bleach and water-based finishes.
Information is from The National Wood Flooring Association
"Wood Species Used in Wood Flooring"