Butt -Base of a tree. Butt log -First log cut above the stump. Also known as butt cut. Butt off -To cut off a piece of a log because of a defect. Buttress -Ridge of wood that develops in the angle between a lateral root and the butt of a tree, which may extend up the stem to a considerable height.
Butt rot -Decay or rot characteristically confined to the base or lower bole of a tree.