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Hand-Lens Key
Species in Key

Hand-Lens Key for the Use of Identification of Important Comercial Woods Used in the Unites States
W. R. Adams, revised by R.A. Whitmore, University of Vermont

Aggregate Ray    A composite of a number of small rays, some fibers and sometimes some vessels together appearing under the lens as a single very broad ray.

Annual Growth    The wood layer laid down during any given year.

Annual Ring    Growth ring.

Bird's Eye    A figure on the tangential surface caused by fiber distortion. There will be numerous small rounded areas resembling a birds eye.

Brashness    Condition of wood that results in breaking quite suddenly and completely across the grain with little splintering when the wood is bent slightly.

Compound Ray    An unusually broad, large ray commonly occurring in oak and Beech, etc. (obsolete)

Cross Grain     Fiber alignment within the wood is not parallel or strictly vertical in standing tree. Interlocking of fibers make wood difficult to split.

Cross Section    Surface of wood at right angles to the run of the grain; a surface of the circular area of the wood cylinder. Same as transverse section.

Diffuse-Porous Wood    Porous wood in which there is little on no variation in the pore size throughout the annual ring.

Early Wood     Portion of the growth ring which is formed at the beginning of the growing season. Also spring wood.

False Ring    A band or streak of thick walled cells appearing darker in color similar to the late wood of the annual ring but which is proceeded and followed in the growth ring by early wood cells. True band of late wood will occur further out in the ring. There may be more than one false ring within a true annual ring.

Fiber    An elongated cell with pointed ends and thick, or occasionally thin, walls occurring in the annual ring.

Flat Sawn    Tangential face shows on the surface of the board. Same as plain-sawn

Fusiform Ray    A spindle shaped ray, quite broad in the middle, Containing a resin canal.

Grain of Wood    Direction of arrangement of wood cells when considered in relation to each other or as a group.

Hardwood    Porous wood produced by broad leaved tree species.

Heart Wood    Dead inner core of wood in a tree usually of darker color.

Late Wood    Portions of the annual ring produced during the later part of the growing season. Also summer wood.

Longitudinal Parenchyma    Cells, the long axis of which is parallel with that Parenchyma of the vessels and tracheids. Usually forms distinguishing patterns within the growth ring which are visible on the cross section. These cells contain protoplasm and are thin walled, storing manufactured food. Also axial parenchyma.

Longitudinal Resin Canal    with long axis of opening in alignment with Resin Canal long axis of wood cells. Cross section of opening seen on the transverse surface.

Lumen    The cavity of a cell. That place where living contents have been or still are present.

Non-porous Wood    Contains no vessels or pores. These are the conifers or soft woods.

Parenchyma    Short, thin walled cells containing living contents in sapwood, storing and distributing manufactured foods, particularly carbohydrates. Parenchyma is dead but contains stored food.

Pitch Pocket    Opening in coniferous woods larger than a resin duct usually at growth increment boundaries which contain or has contained resin. Usually lens shaped.

Pitch Streak     Resin-soaked patches of cells in coniferous woods.

Pitch Fleck    Small areas of wound tissue darker or lighter in color than surrounding tissue. Wounding of the cambium by the larvae of small flies of genus Agromyza causes wound tissue formation or parenchymatous cells which occlude the tunnels.

Plain sawn     Same as flat sawn.

Pore    Cross section of a vessel as it is observed on the transverse section of the wood of broad leaved species.

Porous Wood    Wood containing pores or vessels. Same as hard wood. Produced by broad leaved species.

Quarter Sawn    Boards sawn along the radial surface of a split log or cant from a log so that long axis of rays are exposed on surface of wood. Same as edge grained.

Radial Section    Same as quarter section, or surface; section parallel with long axis of rays, at right angles to growth rings.

Ray Fleck    Portion of the ray as it appears on the radial surface.

Resin Canal    A tube-like intercellular space, in some coniferous woods, sheathed by secreting cells (epithelium) bearing resin in the sapwood. Epithelial cells are dead in heart wood. Resin usually fills the intercellular space.

Resin Tracheid    Tracheid containing deposits of resinous materials.

Ring Porous Wood     Porous wood in which pores are formed in a distinct, conspicuous band or row at the beginning of the annual ring. Early wood pores are usually much larger than the late wood pores.

Ring Shake    A rupture in the wood which occurs between the annual rings. Occasionally shake may occur with in the annual rings.

Ripple Marks    Striations across the grain on the tangential surface of the wood, caused by the storied arrangement of the rays or wood elements forming alternating streaks of light absorbing and light reflecting bands.

Sapwood    Outer portion of a woody stem, usually lighter color than heartwood and containing living parenchyma cells.

Semi-Diffuse     Intermediate between diffuse porous and ring porous wood Porous Wood but larger early wood pores fail to form a distinct ring or band at the beginning of the annual ring.

Simple Ray    Small wood ray usually a single cell in width as viewed in end section on the tangential surface.

Soft Wood    Wood of the coniferous tree species. The wood itself is not always soft.

Specific Gravity    The avendry weight of a block of wood divided by the of Wood weight of the water displaced by the wood at a given moisture content.

Spiral Grain     Fibers are aligned helically around the stem.

Straight Grained    Fiber alignment is parallel and vertical in the standing tree.

Tangential Section    Section cut along the grain at right angles to the rays.

Texture of Wood    Size and number of cells, proportions of large and small cells and number of rays influence texture. Small diameter and numerous cells in a ring usually form a fine textured wood.

Tracheid    Lignified elongated cells. Forming the main wood mass. Cell wall contains bordered pits and forms a bluntly tapering or rounded edge.

Transverse Resin Canal    Extends across the grain and included within fusiform rays.

Traumatic Resin Canal    Resin canal assumed to originate as a result of an injury, usually occurring in peripheral rows.

Tyloses    Sac-like structures sometimes developed in a vessel through the proliferation of the protoplast of a parenchyma cell through the pit pairs.

Unisereate Ray    Ray consisting of a single row of cells as seen on the tangential surface.

Vessel    A tube-like structure in porous woods formed from the fusion of the cells in a longitudinal row through the partial or complete disappearance of the cross walls.