Softwood Lumber & Plywood



Glossary of Common Lumber Terms

A B C D Grades of softwood veneer which are combined in the manufacture of plywood. The best grade is A, the lowest D. Most thicknesses of plywood, when laid up, contain layers of various grades.

African Mahogany A reddish brown, moderately soft wood used in cabinets, furniture and door/window manufacture. Most comes from Nigeria.

After Date of Arrival (ADA) A credit term designation that the invoice on an order is not due until after the shipment arrives at the customer’s destination.

After Date of Invoice (ADI) A credit term used to define conditions of sale. Certain discounts are often granted for payment within a specified period ADI.

After Deducting Freight (ADF) A credit term used in defining terms of payment of invoices. Certain discounts are allowed after a freight allowance is deducted.

Air Dried Seasoned by exposure to the atmosphere, under cover or open to the elements, without artificial heat.

Alder A tree or shrub related to the birches, preferring wet areas. Red Alder is a commonly used West Coast specie, a deciduous tree of the Pacific Northwest, having pinkish-brown wood that is typically used in interior finishing, cabinetry, and furniture.

All Heart Lumber having all heartwood (portion of the tree contained within the sapwood).

Alpine Fir Sometimes referred to as Subalpine Fir, it is a species included in the White Wood grouping.

American Lumber Standard (ALS) A voluntary product standard developed by the National Bureau of Standards in cooperation with consumers, architects, distributors, and producers/manufacturers. It establishes the methods of testing, grading and marking of products, the technical requirements, and the dimensions for lumber produced.

Annual Ring The layer of growth added to the circumference of a tree in one year.

Anti-Stain Treated Wood product treatment with any of various chemicals to retard staining caused by fungi or exposure to weather.

APA Trademark A registered trademark of the American Plywood Association. It signifies that a panel has been manufactured under their quality supervision and testing guidelines.

Aspen Any of several hardwood species of poplar whose wood is used for pulp, in the manufacture of OSB, roofing shakes, and light-colored lumber.

Band Saw A saw consisting of a continuous piece of flexible steel used to cut logs into cants and to rip lumber.

Bark The outermost layer of a tree.

Basswood A fine-textured, softer hardwood specie used in cabinetry, shutters, and paneling.

Birdseye A contortion of the grain in lumber in the shape of a small circle or ellipse, often resembling the eye of a bird. Often this feature is highly desirable for its aesthetic appeal or decorative effect.

Blanked Lumber Lumber surfaced two sides to a size in excess of standard “dressed size” but scant of nominal size. It is usually intended for subsequent remanufacture.

Blue Stain A discoloration of wood caused by a fungus in the deterioration process of a fallen log, usually occurring in the sapwood. It is a troublesome defect common in Ponderosa Pine logs during warmer months.

Board Foot The basic unit of measurement for lumber. One board foot is equal to a 1-inch board 12 inches in width and 1 foot in length. For example, an 8-foot long, 1-inch thick and 12-inch wide board would equal 8 board feet. Nominal sizes are assumed when calculating BF (sometimes referred to as board measure, or BM).

Bow Deviation flatwise from a straight line from end to end of a piece of lumber in an arching fashion.

Boxed Heart A piece of lumber in which the pith, or heart center, is enclosed within the four sides of the piece of lumber.

Bright Free of stain.

Brown Stain A brown-colored discoloration of the sapwood of some pine, particularly Sugar pine, caused by a fungus that thrives in a moist condition with minimal air circulation.

Bullseye Boxed heart. A timber or piece of dimension lumber cut so as to center the pith.

Butt Joint An end joint made by simply joinng the square ends of two pieces of lumber or panel.

Cant A large slab cut from a log at the headsaw, usually having one or more rounded edges, and destined for further processing by other saws.

CD Exterior (CDX) A grade of plywood; the standard grade of plywood sheathing. The “CD” represents the grades of veneer used for the face and back, respectively. The “X” signifies that an exterior-type glue has been applied. However, despite the exterior-type glue, CDX plywood is classified as an interior type of plywood and is required to withstand only incidental exposure to the weather during construction.

Checks A partial separation of veneer fibers, usually small and shallow, running parallel to the grain of the wood, caused chiefly by strains produced in seasoning.

Clear Wood Wood that has no or very limited defects. In some cases, grading rules permit very small knots, pitch streaks or other minor imperfections.

Close Grain Wood grain characterized by an average of about six, but not more than about 30, annual rings per inch on either end of a piece of lumber.

Conifer Any of an order of shrubs or tress (such as pines) that usually are evergreen and bear cones.

Core Gap A space between two adjacent pieces of crossband or other inner ply in a piece of plywood.

Core Void Voids extending through the thickness of an inner ply, usually consisting of knot holes, worm holes, open splits and open pitch pockets. Minute beetle holes are not included in this category.

C-Plugged A C-grade panel face or back that has been patched where there was a defective portion. Such a patch may be sound wood, but is likely to be a synthetic filler of fiber and resin to provide a sound, smooth surface.

Crook Deviation edgewise from a straight line from end to end of a piece of lumber, measured at the point of the greatest distance from the straight line.

Crossband A construction technique for plywood with five or more plies in which veneer is laid at right angles to the core and front and back faces. This increases the panel’s stability. The crossbands are the even-numbered veneers in such construction.

Cross Grain An area in a piece of lumber in which the grain of the wood is distorted so that it runs across the piece from edge to edge rather than along the length of the piece. Often times the deviation of the grain may be around a knot.

Cull 1. A tree of log that is less than one-third usable for lumber or plywood because of excessive decay or other defects. 2. Lumber of the lowest quality, usually below Economy of #5 grade, and must be sorted out.

Dado A groove cut into one piece to accommodate another piece. A dado is three-sided and cut into a board, usually across the grain, as opposed to a rabbet, which has two sides and is at the edge of a board.

Decay Disintegration of wood substance due to action of wood-destroying fungi, also referred to as rot.

Defect Any naturally occurring imperfection, or condition of wood, including open checks, decay, shake, pitch, loose knots, open joints, etc., that would make lumber off grade or interrupting the smooth continuity of the surface in a panel product.

Demurrage A charge assessed by a carrier for holding a rail car, truck, or ship.

Dimension 1. In softwood, lumber from two to four nominal inches thick and two or more inches in width. Also referred to as framing, planks, rafters, and joists. 2. In hardwood, pieces cut to full-inch dimensions.

Double-End Trimmed (DET) Passed through saws to be smoothly trimmed at both ends.

Douglas Fir (Psuedotsuga menziesii) This softwood is found throughout the Western United States and Canada, but grows most abundantly on the western slopes of the Cascade Mountains in Northern California, Oregon and Washington. Prized for its strength, it is used in general framing construction as well as in finish applications and door manufacturing.

Downfall Sometimes referred to as “falldown”, these are pieces that did not meet grade or size requirements.

Dry Seasoned, usually to a moisture content of 19% or less.

Dry Rot A type of decay in seasoned wood, caused by fungi.

Eastern S-P-F Lumber of the S-P-F group produced in the eastern provinces of Canada (i.e., Manitoba and Saskatchewan) and in the northeastern United States.

Edge Banding the process of applying various materials to the edges of panel products for appearance or to provide an edge for hardware attachment or machining. The edge bands may be thin, rigid strips of laminates, metal, lumber, or plastics.

Encased Knot One not intergrown with the annual rings of the surrounding wood.

Enclosed Knot One buried in the wood and not visible on the surface.

End Matched Machined lumber that has been matched with a tongue at one end and a groove at the other end to provide a tight end-to-end fit.

Engineered Wood Products Lumber or panel products manufactured by using adhesives to hold together dimension lumber, oriented veneers, wafers, or wood fibers.

Evergreen A tree that keeps its leaves the year round, usually a conifer or narrow-leaved variety.

Exterior 1. Refers to the type of plywood intended for outdoor or marine uses. This type is bonded with adhesives, affording the ultimate in water and moisture resistance. The veneers are C grade or better. 2. A type of glue-laminated lumber.

Face The better side of a piece of plywood or lumber in regards to quality and appearance.

Fenestral Pertaining to the arrangement or design of windows or doors.

Fingerjoint A machining method of joining two or more pieces of lumber end-to-end by sawing into the end of each piece a set of projecting “fingers” that interlock. When glue is applied and the pieces pushed together, it creates a sturdy glue joint.

Fir Mostly used to refer to Douglas Fir, but also a general term for a variety of conifers, including the True Firs.

Fir&Larch A mixture of Douglas Fir and Western Larch. These species are typically intermixed in the Inland regions of the Western United States and British Columbia.

Flat Grain Annual rings, or grain, that form an angle of less than 45 degrees with the surface of a piece of lumber.

Flitch 1. Thin layers of veneer sliced from a cross-section of a log, as opposed to turning the log on a lathe and peeling the outer edge in a continuous ribbon. 2. A log sawn on two or more sides from which veneer is sliced.

f Rating The measurement of stress, symbolized by the letter “f”, in a piece of lumber. Generally, the higher the rating, the stronger the piece of lumber.

Free of Heart Center (FOHC) Lumber sawn to exclude the pith or center of a log.

Free on Board (FOB) A reference to the point to which the seller will deliver goods without charge to the buyer. Additional freight or other charges connected with the transporting or handling the product becomes the responsibility of the buyer.

Full Sawn A grading term used to describe rough lumber that has been cut to full nominal size.

Furring Lumber one inch in nominal thickness and less than four inches in width, mostly 1×2 and 1×3. Typically fastened to wall studs to provide a nailing surface.

Fuzzy Grain A term used in surfaced lumber when the fibers are not completely severed in the surfacing process, giving it a fuzzy appearance.

Glulam (Glue Laminated) A process in which individual pieces of lumber or veneer are bonded together with an adhesive to make a single piece, with the grain of each piece running parallel to the grain of each of the other pieces.

Grade Stamp An ink-dispensing stamp, issued by a grading agency or association to a client mill or remanufacturer, used to indicate the grade of lumber or plywood, along with other information. Typically, the stamp will include the species, grade, producing mill and/or agency number, grading agency, heat treatment (i.e., “HT”) if applicable, and a designation (for lumber) of whether the stock was dry or green when surfaced.

Grain A general term referring to the arrangement, direction, and appearance of wood fibers. Types may include fine, coarse, open, curly, straight, flat, spiral and vertical.

Green Referring to lumber that is not dry and has a moisture content of 19% or more; unseasoned.

Gross Measure The board measure content of lumber calculated from nominal sizes, as contrasted with a measurement form actual dimensions.

Hardboard A generic term for a panel manufactured primarily from interfelting lingo-cellulosic fibers consolidated under heat and pressure in a hot press; a very dense fiberboard.

Hardwood A general term referring to any of a variety of broad-leaved, deciduous trees. The term has no referral with the actual hardness of the wood-in fact, some hardwood species are softer than evergreen (or softwood) species.

Heart Face The face side of a piece of lumber that is free of sapwood.

Heartwood That portion of the tree contained within the sapwood. This section is dormant and unnecessary for the tree’s continued life. The living part of the tree is contained in its outer parts.

Heat Treatment The process of subjecting wood products to a high temperature for a sufficient or prescribed length or time in order to kill any pests, fungi, etc.

Heavy Dressing (or Surfaced Heavy) A thicker than standard piece of factory grade lumber. For example, “heavy” 6/4 Sugar Pine is 1-9/16″ thick, while standard surfacing is net 1-13/32″.

Hem-Fir A species combination used by grading agencies to designate any of various species having common characteristics. Species included are Noble Fir, White Fir, Red Fir, Grand Fir, Pacific Silver Fir, Shasta Fir, and Western Hemlock. In terms of volume, White Fir and Western hemlock are most prevalent. Sometimes it is classified further under Hem-Fir (Coast), referring to stock produced in Western Oregon, Western Washington and British Columbia and is generally understood to be primarily Western Hemlock. Hem-Fir (Inland) refers to stock produced in Northern and Central California and the Inland West, and is generally understood to be White Fir or a directly related species.

Hit and Miss (H&M) A series of surfaced areas with “skips” not over 1/16-inch scant between them.

Idaho White Pine Another name for Western White Pine, a cousin of the Sugar Pine in California. It is easily worked and is favored for furniture, cabinetry, shelving, and a variety of specialized uses.

Inland Region (or Inland Empire) This region is generally considered to include those parts of Oregon and Washington east of the Cascades, along with Idaho and Montana.

Intergrown Knot One whose annual rings are partially or completely intergrown on one or more faces with the annual rings of the surrounding wood.

Jacket Board A board produced incidentally when cutting a log into lumber. It is usually developed from the first slab cut by the head rig.

Jack Pine This species is found in East Central Canada and the Great Lakes states. It is generally small in size and is used primarily for pulpwood and studs.

Jags Odds and ends left in an inventory; quantities too small to make up a full unit of lumber or plywood.

Kiln A chamber in which wood products are seasoned by applying heat and withdrawing moist air. Sometimes referred as a dry kiln.

Kiln Burn A darkening or scorching on the surface of lumber that sometimes occurs when the lumber is seasoned in a kiln.

Kiln Dried (KD) Lumber that has been seasoned in a kiln to a predetermined moisture content.

Kiln Wet Lumber that has been removed from the kiln before it has dried to the required moisture content.

Knot A branch or limb embedded in a tree and cut through in the process of manufacturing. Knots are classified according to size, quality and occurrence. Size classifications include: Pin knot-not exceeding one-half inch diameter; Small-larger than one-half inch but not over three-quarter inch; Medium-larger than three-quarter inch but not over one and one-half inch; Large-over one and one-half inch in diameter. Quality classifications include: Unsound-a knot containing decay; Encased-a knot whose rings of annual growth are not intergrown with those of the surrounding wood; Loose-not held tightly in place by growth or position; Intergrown-partially or completely intergrown on one or two faces with the growth rings of the surrounding wood; Fixed-a knot that will hold its place in a dry piece under ordinary conditions; Sound-a knot that is solid across the face and shows no signs of decay; Tight-a knot fixed by growth or position so as to retain its place; Firm-a knot that is solid across its face but contains slight decay; Pith-a sound knot containing a pith hole not over one-quarter inch in diameter. Occurrence classifications include: Branch knots-two or more divergent knots sawed lengthwise; Corner knot-one located at the intersection of adjacent faces; Single knot–one occurring by itself; Spike knot-a knot sawed in a lengthwise direction; Cluster-two or more knots grouped together.

Larch (Western Larch) This softwood specie, also called Mountain Larch or Western Tamarack is native to Eastern Oregon and Washington, Idaho, Montana, and the southern interior of British Columbia. It is often intermixed with Douglas Fir since both have similar structural qualities. It is one of two conifers that shed their needles in winter.

Light Framing Lumber that is two to four inches thick, two to four inches wide, and graded Construction, Standard, Stud, or Utility. Mostly as 2×4, it is used in a wide variety of general construction applications.

Lodgepole Pine (Pinus contorta) This species is found in a wide range in the Northwestern United States and Canada. The primary pine in Spruce-Pine-Fir and Engelmann Spruce, Lodgepole is a principal raw material for studs and smaller-sized dimension. It takes its name from the use various Indian tribes made of it. These tall, straight trees were ideal as frames for their lodges.

Low Grade A general term describing framing lumber graded as Utility and #3 Dimension or lower (e.g., Economy, Dunnage).

Managed Forest Forested lands supervised and maintained for several purposes, frequently for maximum timber production. Management includes the harvesting and restocking of timber, protection of wildlife and watershed, and fire and disease control.

MBF The standard abbreviation for “1,000 board feet” of standing timber, logs, and manufactured lumber.

Milling The process of planning or shaping a surface.

Mill Run The normal output of a sawmill. When stock is offered for sale as such, it is understood to be the typical grade mix and tally assortment of the mill.

Millwork Lumber that has been remanufactured into door and window parts or decorative trim and the like.

Minor Bundled Special packaging for smaller pieces of lumber (e.g., 1×2, 1×3) where the pieces are tied together with string, tape, or nylon strapping. The small bundles are then combined in normal-sized units; sometimes referred as sub-bundling.

Moisture Content The weight of the water in wood, expressed as the percentage of the weight of the kiln dried or air dried wood.

Monterey Pine Another name for Radiata Pine and indigenous to the coastal areas of Central California. It has been widely planted in Australia, New Zealand, South Africa, Chile and Spain. In these areas, plantations produce harvested timber in relatively short times, with thirty-year old trees reaching 100 feet in height and thirty-inch diameters. It is not commercially harvested in significant quantities in California.

Moulding & Better (Mldg&Btr) A grade combination purchased by moulding producers. It consists of the grades Moulding, D Select, and C&Btr Select in combination. The percentages of each grade vary from mill to mill. It is primarily graded from stock produced from Ponderosa Pine, Sugar Pine, Radiata Pine, White Fir and Douglas Fir. Much of the lumber is produced in the rough or blanked (i.e., “surfaced heavy”).

Nominal Size The size designation for most lumber, plywood, and other panel products, used for convenience. In lumber, the nominal size usually is greater than the actual dimension. For example, a kiln dried 1×12 is ordinarily surfaced to 3/ 4 x 11-1/4 inches. In panel products, the size is generally stated in square feet for the surface dimension and various increments of thickness.

No Prior Selection A notation on an offering of lumber that indicates that, if the loading is marked with a grade such as #2 & Better, the higher grades have not been pulled out.

Open Grain Lumber which is not restricted as to the number of rings per inch or the rate of growth.

Oriented Strand Board (OSB) A structural panel made of narrow strands of fiber oriented lengthwise and crosswise in layers, mixed with a resin binder. Depending on the resin used, this product can be suitable for exterior or interior applications.

Paint Grade A description of a wood product that is more suitable for painting than for a clear finish.

Paragraph 99 A grade of Ponderosa Pine commons selected to provide shop-type cuttings suitable for fingerjointing by moulding and millwork plants. The name is derived from paragraph 99 of the factory lumber section of the Western Wood Products Association grading rule book.

Partially Air Dry (PAD) Seasoned to some extent by exposure to the atmosphere, without artificial heat, but still considered unseasoned or green.

Particleboard A generic term to describe panel products made from discrete particles of wood or other lingo-cellulosic material rather than from fibers. The wood particles are mixed with resins and formed into a solid board under heat and pressure.

Patches Insertions of a piece of wood or synthetic material to fill defects in plies of plywood; sometimes referred as “plugs”.

Pencil End Trimmed Lumber that is not double end trimmed, but rather has been marked by a pencil or crayon to the desired length and tallied accordingly.

Pitch Pocket A well-defined opening between rings of annual growth, usually containing, or has contained resin, either solid or liquid.

Pith The small, soft core in the structural center of a log.

Plywood A flat panel made up of a number of veneers in which the grain direction of each ply is at right angles to the one adjacent to it. The veneers are united, under pressure, by a bonding agent.

Ponderosa Pine (Pinus ponderosa) A tall pine of western North America, this species is found in a wide range that reaches from British Columbia to Mexico, and from the Pacific Coast to the Dakotas. The wood is widely used in general construction, most often as boards, but is more valued for its uses in millwork and in cuttings for remanufacture.

Poplar Any of a genus of slender quick-growing trees (as a Cottonwood, Aspen, Balsam Poplar) related to the willows.

Radiata Pine See Monterey Pine. Also called Kiwi Pine or Insignis Pine.

Raised Grain A roughened condition on the surface of dressed lumber in which the hard summerwood is raised above the softer springwood, but not torn loose from it.

RWL “Random Width and Length”, an assortment of widths and lengths normally accumulated when manufacturing certain grades and sizes of lumber.

Redwood This species (Sequoia sempervirens) is found only in limited areas of coastal Northern California and Southern Oregon. Another species (Sequoia gigantean) grows in the Sierra Nevada Mountains of Central California. The heartwood of Redwood is resistant to decay and its wood (heartwood and sapwood) is used for many of the same purposes as Cedar, especially siding, decking planks, fencing, and paneling.

Resawn Lumber Lumber that has been sawn on a horizontal axis to produce two thinner pieces. For example, a 2×6 S4S (smooth four sides) that is resawn center would make two pieces of 1×6 S1S2E (smooth one side two edges).

Rotary-Cut Veneer Veneer peeled from a round log by turning the log against a knife to produce a continuous sheet of wood (like a ribbon) of a uniform thickness.

Rough Lumber Lumber which has not been dressed or surfaced but has been sawn, edged, and trimmed.

Rough Full Sawn Unsurfaced lumber cut to full specified size.

Run to Pattern Lumber that has been machined to a particular configuration, such as tongue-and-groove or shiplap.

S1S Surfaced one side.

S2S Surfaced two sides.

S4S Surfaced four sides.

S1S1E Surfaced one side, one edge.

S1S2E Surfaced one side, two edges.

Sapwood The lighter-colored wood occurring in the outer portion of the tree (between the bark and the heartwood), sometimes referred to as “sap”.

Sash The portion of a window that holds the glass.

Saw-Sized Lumber Lumber uniformly sawn to the net size for surfaced lumber, and not planed on the faces, although the corners may be rounded slightly.

Scant Less than standard or required size.

Scotch Pine (Pinus sylvestris) European conifer widely used in reforestation. Also referred as Scots Fir or Scots Pine.

S-Dry A description of lumber seasoned to a moisture content of 19% or less before surfacing.

Seasoned Not green; having a moisture content of 19% or less.

Seasoning Checks Small splits that occur in wood grain if moisture is withdrawn too rapidly.

Second Growth Timber that has regrown after a virgin stand was logged or burned.

Select Tight Knot (STK) A grading term used typically for Cedar lumber. This designates pieces of lumber to have tight knots as differentiated from pieces that may contain loose knots or knotholes.

Shake A lengthwise grain separation between growth rings, usually the result of high winds.

Shiplap Lumber or plywood that has been machined to make a lapped, or rabbeted, joint on each edge so that pieces may be fitted together snugly for increased strength and stability.

Shook Sawn or split pieces of wood used in the construction of barrels or boxes.

Shop Lumber that is graded for the number and sizes of cuttings that can be taken from it. By cutting out the knots or other defected areas, this category of graded lumber is often used in the manufacture of door and window parts.

Shop Outs Shop-type lumber that falls below the official shop grades (e.g., #3 Shop), but will yield some cuttings.

Skip An area on a piece of lumber that a planer fails to surface.

Sliced Veneer Veneer that is cut from a block using a knife, with the resulting slices coming off as individual pieces rather than one long, continuous sheet that results from peeling on a lathe.

Slope of Grain The deviation of the line of fibers from a straight line parallel to the sides of a piece.

Soft Textured A term used by some pine and fir producers, primarily in California and Oregon, to describe their sawn products. Wood from these areas is often finer in grain and softer in texture than wood from areas farther north.

Softwood A general term referring to any of a variety of trees having narrow, needle-like or scale-like leaves, generally coniferous. This term has nothing to do with the actual softness of the wood-in fact some “softwoods” are harder than some “hardwood” species.

Southern Yellow Pine A species group, composed primarily of Loblolly, Shortleaf, Longleaf, and Slash Pines. The SYP region refers to the southeastern United States, from Texas to Virginia.

Spike Knot A knot produced when the limb is cut either lengthwise or diagonally.

Split A lengthwise separation of a piece of lumber extending from one surface through the piece to the opposite surface or to an adjoining surface.

Spruce-Pine-Fir (S-P-F) Canadian and U.S. woods of similar characteristics that have been grouped for production. These species have moderate strength, are easily worked, take paint readily, and hold nails well. The largest volume comes from Eastern Canada where the principal species may include Red Spruce, Black Spruce, Jack Pine, and Balsam Fir. The principal species originating in Western Canada and the Inland Empire of the U.S. are White Spruce, Lodgepole Pine, Engelmann Spruce, and Alpine Fir. Production in the United States is typically identified as S-P-F (S) for “south”.

Square Edged Free of wane and without eased edges.

Square Foot A unit of area measurement equal to a square 12 inches on each side. This is the standard unit of measurement for panel products. A 4 foot by 8 foot sheet of plywood of any thickness would contain 32 square feet.

Stain Discoloration on or in lumber other than its natural color. Stain may be caused by fungal growth, weathering, or the oxidation of metallic substances in a log. It is classified for grading purposes as light, medium, or heavy.

Standard Surfacing The surfaced size of a piece of lumber established in grading rules. This phrase is usually used in reference to shop lumber, which can be surfaced to a variety of thicknesses to meet specific customer needs. For example, 5/4 Shop is 1-5/16″ in thickness when “Surfaced Heavy” and 1-5/32″ in thickness with “Standard Surfacing”.

Struc I A grade of strength-rated plywood or OSB often required by building codes in regions of high winds or seismic activity. Struc I plywood requires all Douglas Fir veneer with a C-grade core. OSB Struc I panels require more wax and a longer press time, resulting in a stiffer panel.

Sturd-I-Floor A trade name registered by the APA for a panel designed specifically for use as combined subfloor / underlayment in residential floor applications. It is available in several thicknesses, each keyed to a recommended spacing of floor joists from 16 to 48 inches.

Sugar Pine (Pinus lambertiana) This species, found principally in Central and Northern California and Southern Oregon, is light, smooth, soft textured, and easily worked. It is popular in millwork, pattern work, and various interior applications. It takes its name from the sugary, sweet-tasting deposits of resin that are exuded from its bark after injury to the tree.

Surface Measure A method of measuring an area that gives a measurement of area only and does not take thickness into account. For example, a 2×6 ten feet long would measure five square feet on a surface measure basis, but ten board feet on a board foot basis.

Tally Stick A device used to tally shop lumber. It consists of a wooden stick with marks showing widths multiplied by lengths.

Torn Grain A surface irregularity in a piece of lumber caused when the wood is torn out during surfacing.

Twist A deviation from the flat planes of all four faces of a piece of lumber by a spiraling action, usually the result of drying.

Unseasoned Lumber that has not been dried to a specified moisture content before surfacing. Generally, lumber that has a moisture content exceeding 19%.

Unsound Wood Containing decay.

Veneer A thin sheet of wood, rotary-cut, sliced, or sawn from a log, bolt or fletch. Veneer may be referred to as a ply when assembled into a panel.

Veneer Patches Patches inserted in veneer sheet before panel is assembled for pressing.

Vertical Grain (VG) Lumber that is sawn at approximately right angles to the annual growth rings so that the rings form an angle of 45 degrees or more with the surface of the piece.

V-Groove A pattern applied to tongue-and-groove lumber in which the edges of the pieces are chamfered so that a V-shaped groove is formed on the surface where the two pieces meet. A V-groove may also be machined into the face of a piece of lumber or a panel.

Waferboard A structural panel product made of discrete, randomly oriented wafers of wood bound together by resin, heat, and pressure. Waferboard has been largely superseded by OSB.

Wane Bark, or the lack of wood from any cause, on the edge or corner of a piece of lumber.

Western Woods A species designation that, under current grading rules, may include any combination of western softwood species, converted to lumber.

White Fir (Abies concolor) The most important of the True Firs, this species is found in a wide range in the Western United States. The greatest concentration of production in this species is in Northern California. The wood is straight-grained, fine-textured, and relatively light. It is used in general construction and for such specialized uses as doors and mouldings.

White Speck Sometimes referred as honeycomb, it is a condition caused by a fungus in the living tree. It is characterized by small white pits or spots. Honeycomb is an advanced stage of white speck. Neither condition is subject to further decay unless the lumber is used under wet conditions.

White Wood A designation applied to a number of species, such as White Fir.

Wormy A term used to describe wood that has been attacked by any of a variety of borers.

Worst Face The back, or poorer face, on a piece of lumber.