As within any economic sector, the logging and forest-product industries have their own industry language, terms and nomenclature. Below is a list of some of the more common words and phrases you’ll come across when dealing with the hardwood lumber industry.
Board Feet
A Board Foot is a unit of volume commonly used in the hardwood lumber and logging industries. It is equivalent to a piece of wood one foot wide, one foot long and one inch thick, or 144 cubic inches.
Standing timber buyers and sawmills alike use board feet as the standard unit of measurement.
Bow
A lumber defect where a board is physically bowed, making the usable volume greatly reduced. This can be caused by improper drying or wood grain tension.
Buck
Bucking is when trees that have been felled are cut into lengths to be marketed at a timber sale. Doing this correctly directly impacts your bottom line on your timber sale.
Butt Log
The first 8 to 16 feet of a tree trunk depending on quality. The Butt Log typically contains a majority of the value of a tree.
Cant
A log that has been squared off in order to be resawn into dimensional lumber.
Casehardened
Caused by improper drying. Board interior is under competing tension with board exterior. Casehardened lumber is typically no longer suited for most typical applications.
Clearcut
A timber harvesting method resulting in the indiscriminate cutting of all trees at a site, regardless of size, species or quality. This takes place when a wooded lot is developed for residential or commercial purposes.
Deciduous Trees
Trees that lose their foliage seasonally in autumn.
Delimber
A machine for removing limbs from harvested trees.
Form Class
Gauges the straightness of trees contained in a stand. Timber stand value improves with form class.
Grade
A quality rating assigned to a wood product as specified by an independent grading authority. Common grades are FAS, 1 common, 2 common and pallet.
Price of lumber increases as the lumber grade increases.
Hardwood
In the lumber industry, hardwood refers to wood that comes from deciduous trees, which are typically broad-leaved and shed their leaves annually. These trees are angiosperms (flowering plants), and common hardwood species include oak, maple, cherry, and walnut.
Green Lumber
Lumber that has been sawn, but not kiln-dried.
Heartwood
Wood from the inner portion of a tree. In most species heartwood is less desirable than sapwood. In a select few such as Hard Maple, the sapwood is actually more valuable.
Knot
Circular portion of a branch that becomes embedded in a tree as the trunk grows around it.
Log Scales
A scale is used to quantify log volume. Doyle, Scribner and International are the most common log scales utilized in the US. These scales measure tree volume standing and on the ground.
Dimensional Lumber
A value-added product produced by cutting trees into standardized, dimensional boards.
Pith
The core of a tree or branch. When a log is sawn into dimensional lumber, the pith must be cut out of the boards and discarded.
Quartersawn
Quartersawn lumber refers to a specific method of cutting logs into boards that results in distinct grain patterns and improved strength, durability and enhanced grain pattern in some species. In quartersawn lumber, the log is first cut into quarters, and then each quarter is sawn perpendicular to the growth rings. This creates boards where the growth rings are generally oriented between 60° and 90° to the board’s surface.
Quartersawn lumber is more dimensionally stable compared to other sawing methods, such as plain sawn. It is less likely to warp, cup, or twist over time, making it ideal for applications where stability is necessary such as furniture, flooring and musical instruments.
Knots
- Tight Knot: A knot that is firmly embedded in the surrounding wood. This happens when the branch was still alive and attached to the tree as the trunk grew around it. Tight knots usually remain secure within the wood.
- Loose Knot: A knot where the branch was dead before the surrounding wood formed. These knots are not as securely bound and can sometimes fall out or loosen, creating voids in the wood.
In timber and lumber alike, knots can decrease the value of the dimensional lumber
Sapwood
Tree sap circulates through a tree’s vascular system, transporting essential nutrients, water, and sugars throughout the tree. It plays a crucial role in the tree’s growth, health, and survival.
Sapwood is the fiber closest to the trees bark and is seasonally dynamic, moving around the tree
After the sap has fallen in autumn is the ideal time to harvest timber, especially for some species like black walnut.
Spalting
Dark streaks in wood resulting from the introduction of a particular strain of fungus. There are many species can be spalted, and the wood is prized for it’s distinct appearance.
Veneer
A veneer tree is a perfect specimen—they are tall and straight without knots or limbs. Only trees with high-grade wood are typically used for veneer production. The wood must have minimal defects, such as knots, cracks, or irregular grain patterns.
Wood Pulp
Timber with a diameter of less than 14 inches is typically bought as pulp wood. This timber is mechanically broken down and processed into products such as paper, pallets or firewood.