A simple and accessible tool for understanding the fundamental terms related to wood. From the meaning of sapwood and heartwood to the characteristics of texture, grain, and density. A useful resource for professionals, citizens, and students who want to familiarize themselves with the language of the sector.
1) A product made by the mutual bonding of two or more layers of the same or different materials. 2) A term sometimes used to refer to the process of bonding the above product. It is an Anglicizing term, not to be confused with metal lamination.
It consists of bending two or more sheets or laths to the desired shape and, at the same time, gluing them together along the contact surfaces to form a single piece.
Laminated wood in which the individual layers are plywood layers.
A product similar to the “parallel strand lumber or PSL” except that the stands are about 30 cm long, much shorter than those used for the PSL, and its production involves the use of steam injection pressing.
Planar element consisting of mechanically fixed, prestressed or glued timber components, oriented parallel and comprising only fibres parallel to the grain.
Boards, typically finger-jointed, that are part of a glued laminated timber or glued solid wood.
Core plywood in which the core consists of strips of sheets, less than 7 mm thick, arranged in shear and all or most of which are glued together. According to the new European regulations, laminated plywood is now, to all intents and purposes, a category of plywood.
Small parquet element with unshaped edges.
Open area adjacent to a truckable or tractorable road passable by vehicles. This is where timber is brought in by extraction and, where possible, conveniently loaded onto vehicles intended for transport.
Wood species Scientific name: Tabebuia ipè Standl. (= Tecoma ipè Liais). Origin: Southern Brazil, Northern Argentine
A joint obtained by juxtaposing part of one piece over part of the other and gluing the two surfaces together.
Synthetic or natural material consisting of resins. It is applied to surfaces in order to coat them with a film.
Wood species Scientific name: Larix decidua Mill. (L. europaea DC.).
Finger joint along the entire cross section at the ends of glulam components bounded by a ? angle between 45° and 90° (inclusive).
Developmental stage of an insect between egg hatching and pupa formation.
Tunnel carved into wood by insect larvae.
Portion of the growth ring that forms during the late growing season. It generally consists of denser and mechanically stronger wood than that which forms early in the growing season.
A term used to describe the slit-shaped traces (which appear in seasoned wood) decurrent radially through the wood of certain trees provided with latex (especially Alstonia sp. pl. and Dyera sp. pl. of the Apocynaceae). They are characterized by the presence of latex tubes and have their origin in the foliar traces and axillary buds. They are incorrectly called latex canals and latex ducts.
Latex included in a ray. Note: Tubes are modified cells or series of cells, not intercellular canals.
Small square-sawn assortment that, according to Italian standards, has a length of 2 to 4 m and a rectangular cross-section (with a maximum ratio of 2:1 between width and thickness) or a square cross-section with cross-sectional dimensions varying from 1 x 2 cm to 3.5 x 5 cm or 4 x 4 cm.
Elongated piece of sawn timber having a thickness less than 40 mm and a width less than 80 mm.
1) Thin strip of wood, used in the composition of the core of laminboard. 2) Each of the boards that combine to form a glued laminated timber member; 3) In dendrochronology, narrow and very thin strip of wood, whose plane is perpendicular to the direction of the grain. It is obtained from a core or cross-section and used in radiodensitometry.
A chipless cutting machine adapted to obtain, from a rough workpiece, a solid of revolution. The workpiece is rotated against the tool, which moves (either manually or automatically) transversely and longitudinally in such a way as to draw a given shape, which will correspond to the contour of the workpiece.
A chipless cutting machine used for wood peeling.
Cracks parallel to the grain of veneers (and sometimes in thick veneers) that occur during cutting due to the slashing action of the knife. They affect the surface of the sheet that is in contact with the cutting edge (with its face) and will give rise to the “loose side.” The surface of the log that, simultaneously, is also in contact with the cutting edge (with its back) remains relatively intact and will result in the “tight side” of the next sheet.
Cortex formed during late stages of the season. In typical cases it consists mainly of cortical parenchyma and only of sparser, smaller sieve tubes or sieve cells. At the end of the season there is sometimes a terminal layer of fibers.
Wood species See “meranti”.
n the wood-based products industry, the term is used generically to refer to the organization of a mat or assembly of wood elements, their possible arrangement in layers, their orientation or different density. In the plywood industry, the term indicates, for example, the stage in the production process where sheets or layers of other material are assembled to form a package after some of them have been glued (spread with adhesive mixture) and before pressing. The same term is also used to indicate in detail the way the plies are assembled and/or the thickness of the plies used, e.g.: 4-sheet/3-layer composition, with face and back of 2.5 mm.
In a plywood, this term indicates either one or more adjacent sheets glued together with the grain decurring in the same direction, or a material other than solid wood or sheets of wood. For example, a 4-sheet plywood is almost always composed of 3 layers, in which both inner sheets are arranged with the grain parallel to each other and perpendicular to that of the panel faces. These two sheets constitute one layer and each face another. In a composite plywood the inner portion (core) constitutes one layer and each face another.
Pre-assembled flooring elements, joined by a special material, which reproduce a certain geometry.
Removal of soluble substances from wood by the action of water.
Treatment consisting of submerging the wood in water for a prolonged period of time. The aim is to remove part of the substances contained in the cellular cavities.
Humidified air exiting the wood pile during circulation within the kiln.
Element that, when seen from the face with the edge tongue facing the observer, has the leading tongue on the left.
Harvesting in accordance with the applicable legislation in the country of harvest.
Wood species Scientific name: Nothofagus pumilio Kras. ATIBT nomenclature: Lenga. Origin: South America (Argentine and Chilean Andes).
Generally, this term indicates the largest dimension of a product. In the case of round timber, it means the shortest distance between the two end grains. In the case of plywood, the panel length corresponds to the dimension parallel to the grain of its face.
Specialized portion of the periderma of varying shape but often lenticular. Consists of weakly connected cells that are never suberized or weakly suberized and serves for gaseous exchange across the periderm, which is otherwise impermeable.
Fungus belonging to the Basidiomycetes. It causes brown rot to softwood and hardwoods. It is creosote resistant.
Elongated cell, generally with thick wall, with simple pit. It is generally definitively longer than that of the cambial initial, deduced from the length of the vessel elements and parenchymal rows.
A document by which a certification body concedes the right to use certificates and marks of conformity.
Person or body to whom a certification body has granted the right to use certificates and marks of conformity.
Sequence of the various developmental stages of an organism, from egg to adult. Conventionally, it is considered the time between the egg laying of two successive generations.
Ensuring that every component or phase of a product’s life cycle (from raw material to production, packaging, use, and replacement (e.g., through recycling)) is compatible with environmental protection regulations.
Formulation of active ingredients in a volatile organic solvent, e.g. white spirit
See “growth temperament”.
Wood species Scientific name: Dialyanthera spp., Virola surinamensis (Rol.) Warb. Origin: Central America, Venezuela, Northern and south-eastern Brazil.
See “lightning shake”.
Lateral split of a log caused by lightning.
Lignocellulosic material from bark, shrubs or monocotyledonous plants that cannot form wood due to the absence of the cambium. Some examples are: bamboo, rattan
Product in which at least 75 per cent of the total weight is determined by lignified material other than wood components.
It is the second most abundant constituent (after cellulose) of wood. It is mainly located in the middle lamella and primary wall of wood cells. Chemically, it is a complex and irregular amorphous polymer with substituted propyl-phenol groups. It has the function of stiffening the wood cell walls and cementing the cells together.
Wood species Scientific name: Guaiacum officinale L. e Guaiacum sanctum L. Origin: Antilles, coastal areas of Central America, Colombia and Venezuela.
Trace, on the ground or on paper, locating a yarder installation.
See “foot”.
Variation in the length of a semi-finished product or wood-based product resulting from changes in its moisture content.
In wood flooring elements, it is the top or bottom edge surface of the groove.
In wood flooring elements, it is the deviation in height between the faces of two adjacent elements.
Wood species See “american whitewood”.
Goods placed on a transport vehicle.
Element intended for use in a load-bearing construction, an organized interlocking assembly of elements designed to impart mechanical strength and stability to the work.
Sweep resulting from the breakage of the top of the tree.
Wood species Scientific name: Pinus contorta var. latifolia Wats. Origin: Western parts of the United States and Canada, from Alaska to California.
In band saws or circular saws, this is a frame installed on rails and fitted with jaws and other equipment to hold or turn the log. It holds the log during sawing and moves it to the saw in a back-and-forth motion. In multi-blade reciprocating saws, it is a similar carriage that moves the log toward the blades and carries the boards away.
Equipment used for clamping one log at a time on peeling lathe chucks after eventual profile surveying and optimizing the position (or centering) of the workpiece using mechanical, optical or electronic systems. More modern systems are equipped with scanning systems, to detect the exact profile of the topo, and a computer that determines the position corresponding to the best processing yield by controlling the operation of the loader. Among these, the X-Y loader is so called because it is capable of moving the log along an X and Y axis.
Timber intended to be squared with an axe. The name derives from the custom of marking the track to be followed using a wire smeared with carbon black.
A grapple, usually operated hydraulically, installed at the end of a hydraulic knuckle-boom loader or at the rear on the hydraulic lift of tractors. It is used for collecting or loading wood or timber.
Conversion tables that give the probable amount of sawn timber that can be obtained by sawing from one or more round timber. These are used in Anglo-Saxon countries for measuring logs, and they depend on multiple factors (type of sawing, blade thickness, etc.). Several types of such tables, which the British call “log scales,” exist (Doyle, Scribner, Spaulding, Maine, Tieman, etc.).
Treatment of freshly felled logs with wood preservatives to provide temporary protection against attack by insects or sapwood fungi, or both
Storage area for material (roundwood or sawn timber). It also represents the starting point of the production process.
See “log”.
Segment of a log that has been cut to an appropriate length for further processing (sawing, peeling, etc.).
Operation by which a forest stand is felled and partially or fully harvested. Includes felling, processing, extraction, transportation of timber, and related work (often synonymous with forestry work). In the plural it also indicates that branch of professional activities and forestry science concerned with the felling and processing of forest products.
Plywood panel in which the grain of the faces is parallel, or nearly parallel, to the largest dimension of the panel.
Uncut round timber.
In wood products industry, it indicates the direction parallel to the grain.
Shear deformation occurring parallel to the longitudinal axis of an element subject to bending.
Wood shrinkage in parallel direction to the fibers.
Wood swelling in parallel direction to the fibers.
Maximum gauge of an element measured over a length of 2000 mm.
Plywood in which the wood grain of the outer layers is oriented in the direction of the longer side (longitudinal plywood) or in the direction of the shorter side (transverse plywood).
Dead knot that is no longer connected to the surrounding wood.
In veneering, the term refers to the surface of the sheet that is in contact with the face of the knife during cutting and therefore can be affected by peeling cracks. The term derives from the fact that the aforementioned surface is slightly less than the opposite (tight side) so that when the sheet is laid on a support plane, it is subject to stresses of tension perpendicular to the grain. Occasionally, the same definition also applies in the case of slicing, although with lesser effects, especially when thick veneers are obtained.
Veneer with pronounced cracking caused by the action of the sheeter knife and which, therefore, proves to be excessively flexible.
Any number of semi-finished products that can be considered as a single group in relation to a reference legislation.
When the wood species is highly resistant or durable or the environmental conditions of application are not conducive to biodegradation.
Controlled drying (kiln/artificial/technical) with temperatures not exceeding 45°C.