Using the rope isn't even needed for most trees. When you learn how to fell a tree with an axe or saw, you'll learn that you can alter where you make your first cut to account for the tree's center of mass, lean, asymmetric branches, and other obstacles.
For example, if the tree is leaning strongly in one direction and you want it to fall somewhere else 10 degrees away, you basically make your first cut a full 20 degrees away so that it'll split the difference.
If you want a really unsafe way to fell a tree, you can attach a grip hoist 15-20 feet up the trunk and anchor the other end to the bottom of another tree near where you want it to fall. Once you start tightening up the grip hoist, you put enormous torque on the trunk and pull it over. Or the trunk snaps in two. Or your grip hoist breaks.
Disclaimer: if you're learning how to fell a tree from a cigarette card or comments on the Internet, you'd better know a good surgeon.
For example, if the tree is leaning strongly in one direction and you want it to fall somewhere else 10 degrees away, you basically make your first cut a full 20 degrees away so that it'll split the difference.
If you want a really unsafe way to fell a tree, you can attach a grip hoist 15-20 feet up the trunk and anchor the other end to the bottom of another tree near where you want it to fall. Once you start tightening up the grip hoist, you put enormous torque on the trunk and pull it over. Or the trunk snaps in two. Or your grip hoist breaks.
Disclaimer: if you're learning how to fell a tree from a cigarette card or comments on the Internet, you'd better know a good surgeon.