The term sawlog is a log of suitable size for sawing into lumber, processed at a sawmill.
[1] This is in contrast to those other parts of the stem that are designated pulpwood.
Sawlogs will be greater in diameter, straighter and have a lower knot frequency.
Sawlogs most often come from the "butt end" of the stem and are the most financially valuable part of the tree.
This article about forestry is a stub.