Hard maple includes sugar maple (Acer saccharum) and black maple (A. nigrum). Sugar maple is also known as hard and rock maple, and black maple as black sugar maple.  Maple lumber is manufactured principally in the Middle Atlantic and Great Lake States, which together account for about two-thirds of production.  The heartwood is usually light reddish brown but sometimes considerably darker. The sapwood is commonly white with a slight reddish-brown tinge. It is roughly 7 to 13 cm or more (3 to 5 in. or more) wide. Hard maple has a fine, uniform texture. It is heavy, strong, stiff, hard, and resistant to shock and has high shrinkage. The grain of sugar maple is generally straight, but birdseye, curly, or fiddleback grain is often selected for furniture or novelty items.  Hard maple is used principally for lumber and veneer. A large proportion is manufactured into flooring, furniture, cabinets, cutting boards and blocks, pianos, billiard cues, handles, novelties, bowling alleys, dance and gymnasium floors, spools, and bobbins.