Chipped grain means that a part of the surface is chipped or broken out in very short particles below the line of cut. It should not be classed as torn grain and, as usually found, shall not be considered a defect unless it is present more than 25% of the area.
Loosened grain means that a small portion of the wood has become loosened but not displaced.
Torn grain means that a part of the wood is torn out in dressing, and in-depth is four distinct characters; slight, medium, heavy and deep.
The medium torn grain is over 1/32”, but not more than 1/16” in depth.
Skip is an area on a piece that failed to surface. A heavy skip is one that the planer knife did not touch.
Machine burn is a darkening or charring of the wood due to overheating by the machine knives.
Machine gouge is a grooving across a piece due to the machine cutting below the desired line of cut.
A sound knot is solid across its face, as hard as the surrounding wood, and shows no indication of decay.
A medium knot is one over 3/4”, but not more than 1.1/2” in diameter.
A pith knot is a sound knot with a soft center not more than 1/4” in diameter.
Peck is decay which appears in the form of a hole, pocket, or area of soft rot usually surrounded by sound wood. Slight peck is not through the piece occupying less than 10% of the surface area.
Decay is a disintegration of the wood substance due to the action of wood-destroying fungi and is also known as dote or rot.
Machine bite is a depressed cut of the machine knives at the end of the piece.
A shake is a lengthwise separation of the wood, which occurs usually between and parallel to the rings of annual growth.
A check is a lengthwise separation of the wood, which occurs usually across the rings of annual growth.
Wane is bark, or the lack of wood or bark, from any cause on the edge or corner of a piece.
Pith is the small soft core in the structural center of the log.
Pitch is an accumulation of resinous material.