First European Quality Grading Rules
Must be free of the following defects:
Large knots, large bee holes, sun cracks, large pitch or bark pockets, large chalk pockets, inbark, soft heart center, sap, cross or sloping grain, shake, rough grain (wild growth), splits, serious mechanical injury excessively curly or wavy grain, unless otherwise specified.
In pieces that possess lengths or widths not less than the average dimension of a parcel of timber, except pieces with lengths from 9’ upward or widths from 9” upward, which shall be reckoned individually, the following defects will be allowed: One knot ½” in diameter not penetrating to the other side, or one bee hole ¼” in diameter not penetrating to the other side, and pieces carrying each of such defects should not exceed 5% of the total number of pieces in the parcel.
Definitions:
Bark Pockets: Patches of bark partially or wholly enclosed within the wood, aka “inbark”.
Bee Holes: Holes in the wood caused by the larvae of Xyleutes ceramica.
Black Streak or Oil Streak: Black lines. These are present in some pieces. It is considered a defect from the point of view of appearance but does not effect the strength of the timber.
Blemish: Any feature that mars the appearance of a piece of timber but does not effect the strength of the timber.
Chalk Pockets: Cavities in wood that have become wholly or partially filled with white chalky substance.
Chalk Veins: Whitish lines that are present in some pieces. They mar the appearance of a piece of timber but do not affect the strength of the timber.
Checks: Separation of the wood fiber in a longitudinal direction not penetrating to the far end of the piece.
Defect: A feature that reduces the economic value of the piece of timber by decreasing its strength, appearance or workability.
Curly Grain: A wavy growth of the fibers that is difficult to plane or work.
Wavy Grain: Also known as fiddle back grain.
Cross Grain, Slope or Inclined Grain: The principle wood cell deviating more than 10 degrees to the longitudinal axis of the piece of timber (1:5 slope).
Heart Center: The small soft core occurring in the structural center of a log around which the growth of a tree is formed.
Knot: A portion of a branch that has become embedded in the wood, and shows a clear pit in sawn timber. The cross section of a knot is usually circular or oval in shape and is measured by the average diameter. Sound knots are solid across the face except for its pith and is as hard as, or harder than, the surrounding wood to which it is firmly joined. Unsound knots are softer than the surrounding wood due to decay. If the decay is advanced there may be a hole in the center of the knot. Spike knots are caused by a portion of the epicormic branch found imbedded in the wood and appearing in spike form on one of the broad faces.
Sapwood: The outer band of living cells in a tree that are engaged in sap conduction and food storage. This is often of a different color and not as durable as the heartwood.
Shake: A serious split or deep check.
Split: A longitudinal separation of fibers that extend to the opposite face or the adjoining end of a piece of timber.
Spring: Curvature such that if the piece is laid on edge, it forms an arch.
Sun Cracks: Cracks caused by surface checks. Often accompanied by discoloration along the line of the crack.
Wane: Bark, or the lack of wood, on the edge or corner of a piece of timber usually caused by a portion of the original curved surface of the log.