The top cut is the first of two cuts that result in a V-shaped notch. The notch is made on the side of the tree that you want it to fall. Here is the procedure for making a top cut:
Starting Point -- Begin at any height as long as you allow enough room for the undercut.
Angle of Attack -- Cut downward at an angle consistant with the type of notch you are making. Many people use the Humbolt notch which uses a horizontal top cut and allows for using the saw's sight.
Ending Point -- Stop when the cut reaches ¼ to 1/3 of the trunk's diameter or when the cut reaches 80% of the tree's diameter at chest level.
Making the Conventional Cut - OSHA
The Bottom Cut
The bottom or undercut is the second of two cuts that result in a V-shaped notch. The notch is made on the side of the tree facing the direction that you want it to fall. Here is the procedure for making a bottom cut:
Starting Point -- Begin at the level that will create at least a 70 degree notch opening.
Angle of Attack -- Cut upward at an appropriate angle - 20 degrees for an Open-face notch.
Ending Point -- Stop when the cut reaches the end point of the face cut.
