We call this butt or stump roping, and using a chain to do it is a potentially dangerous idea, especially if your cutting so high. From the pic it looks like youve put alot of shock loading on the chain unnessesarily by cutting that high. But youve got the right idea.
Generally we use heavy slings, heavy rope (at least 20mm) or steel cable. We try to tie them in such a way that we can release them even if loaded as it can be VERY hard to get the weight off a big tree heading downhill. Biggest I have done was 6 foot in diameter, wielded my 5 inch line solid to itself, but it held! I scarf, then tie in the buttrope, and keep the rope as short as possible.
Firstly when working on the steep stuff you want to put as little stress on the buttrope as possible. I generally scarf as low as I can with the most open scarf I can manage (usually 90 degrees but I have flat faced a tree to avoid the scarf closing and snapping the hinge). This is so when the tree goes over the hinge wood holds, if done right you want the trunk when it comes over to lay on the ground without breaking the hinge. And if it does break the buttrope catches it (without putting excessive force on the buttrope)
Secondly you want, if possible, for the tree to come over as slow and straight as possible, most of the time trees are weighted downhill so they dont need alot of encouragement but a bit of wedging can help. The reason for the straight path is to help avoid it twising and breaking the hinge.
And last, be careful of the lay of the ground that your falling on, an even contour is fine, but if its a sharp hit like over a bank the trees butt can kick up in a huge way, it can break the head off, snap the buttrope or even tear the stump out. Also be aware that alot of tree shrapnel can end up blasting downhill when the tree hits.
Be VERY careful and get well clear once it starts moving.
Im no expert but do alot of work on steep ground.
