 A properly constructed and sufficient undercut is necessary to fall any tree or snag. When properly constructed, it allows the tree to fall in a predetermined direction to a predetermined lay. Now, we have laid out a ribbon on the line here to indicate the predetermined lay so that we can demonstrate to you the positioning of the Sawyer. We've also taken and shaved some bark off the tree and put a couple of marks on here that we'll explain. The first thing after you've assessed the lean of the tree, and we've already assessed this tree for overhead hazards, its lean in its direction, and determined by the ribbon where it will go. The first thing that the faller needs to do is to position themselves centered on the tree at 90 degrees to the predetermined fall. And when in this position, the faller can determine where he's going to place his undercut. One third to diameter, bring back your gunning cut, and at the same time we can determine the width of our holding wood or our hinge and where our back cut will end. And we know that we don't want to compromise or make any cuts in this section of wood in this process. Making level cuts is an essential part of the falling process. And in this process, we're going to show you how to put in a conventional undercut. To hold your saw level, if you're going to hold a saw like this, it's pretty hard to get a level cut. The saw is awkward and heavy. If you use your full wrap bar or your side wrap here, you can put the pistol grip in your hip, leaning slightly back, looking over the top of the bar, you can determine that it's level. When you've got it in this position, you start the chain moving about one third of the RPMs. And when you just start moving, you start cutting here. As the saw cuts in, we'll draw it back to this point. And when we reach that point, we'll dog in with our dogs and then we'll pivot the saw around until our gunning sights on the saw align with our predetermined fall. When you finish your gunning cut, get back, double check your sight, make sure your alignment is good. After completing the gunning cut, the next cut is the sloping cut on the top. Pull your saw out, hold your saw at about a 45-degree angle, starting at this point. Start your cut up here, as we did with our gunning cut. Forward the mark, start cutting. Draw your chain down until you meet, dog in and start pivoting around. When you're about bar depth in, we'll stop and we'll go around and we'll check the other side of the tree for the alignment. You come around to this side of the tree and see your alignment. A trick that you can use is to take a small twig and place it in the far corner of your gunning cut. By doing this, you can look over your bar and you can see the position of your bar in relation to that stick and see how you're going to come out. If you position yourself like this so that you can only see chain on the top of the bar and you can't see either side of the bar and look at that in relationship to the stick, you'll see that you're going to miss. To correct this, all we need to do is back our saw out to the top of the cut, change the angle of the bar and begin the cut in the cut that we've already established because we've set this corner up and we don't want to change it. We don't want to start another new cut. We just want to correct the angle of the bar in this cut here and start our cut down. This completes your undercut. You can see we've matched our corners up. We don't have any Dutchmen through the center. We have a good 45, a good wide opening and now we're ready to start the back cut. How do we line it up? How do we know that we got the proper stump shot, the proper height? If we're back here, we can't see our undercut so we don't have any idea where we are. We're just guessing that we're going to come out on the other side. Same as if you try to start on the far side over here, you're guessing on that side. If you position yourself about where you started your undercut, where you can see your gunning cut, you can put your saw again using your side wrap bars. You can use your knee if you want. Set the bar so that it's level. You can see that it's level with the undercut. And we know we need about three inches or four inches of stump shot on a tree this size. So we just pick it up. We start our chain running. Start cutting in. Look to the point here that we determined would be our holding wood in the beginning. Dog in and start pivoting our saw around. When we get in far enough to set our safety wedge in, we'll set our safety wedge and we'll go around, look the other side and see how we're coming out. Then we'll come back here, start to saw and we'll follow our gunning site as we pivot the saw around as it begins to line up with our predetermined lay over here. Before starting any back cut on a tree, you need to check your felling security again. Make sure that nobody's entered the area and you need to give a good call. Let everybody know that a tree is coming down now. Tree firing! Okay, as you can see our tree went to the intended lay. The cuts that we made to construct the hinge to lower the tree in that direction, our gunning cut on our undercut and our back cut here are perpendicular level with each other. We have the appropriate stump shot and you can see by the lines that we scribed and we started that we followed our plan and constructed our hinge in the appropriate place and we didn't cut anywhere into this while we were doing our undercut or our back cut and we were able to put our tree in the way. We hope that these tips are helpful to you and help you understand the principles of falling so that you can safely perform your job on the fire line.