Words can have a variety of meanings when used by different people. Wood science textbooks tend to agree on the definition of the words heartwood and sapwood. Trees transform sapwood into heartwood by depositing additional chemicals in the wood. The color and durability of heartwood make it preferred for many products.
In informal speech ‘heart pine’ (or sometimes ‘heart of pine’) is often used to describe wood products containing the heartwood of southern yellow pine trees. Traditional heart pine floors were all heartwood. Now many products labeled heart pine actually contain a mixture of heartwood and sapwood. As the color of the wood matures the heartwood develops a much deeper color whereas the sapwood remains yellow. The contrast increases between the heartwood and sapwood as the wood ages. According to the Southern Forest Products Association website ” there is no set ratio of heartwood vs. sapwood in the grading rules that defines heart pine lumber.” The site goes on “Of the 10 Southern Pine species, longleaf pine is most commonly referred to in the trade as “heart pine”. It is generally characterized by tighter growth rings, higher density and greater proportion of heartwood. Longleaf lumber is so prized it merits a special quality classification within the grading rules.”
The superior qualities of longleaf pine heartwood enhance both the appearance and durability of products made from this wood.