Stump grinding is when you remove the whole stump from your yard, and then replant it somewhere else. You might have heard this method called "rooter-less planting", but it is not the same as just putting a new tree in the ground. A rooter simply takes the roots of the tree out of the ground and re-places them into a hole. So how close can you really be to the stump before you remove it?
Some people feel that they can take down an old tree. If they can do it by hand then they are closer than most people to doing it with a stump grinder. But some people simply don't have the time, or don't feel confident in their abilities, to remove the whole stump and replace it with a new one. In these cases a stump grinder can make things a lot easier.
The biggest factor when it comes to how close can you plant a tree to a stump is your ability to dig it up. If you have a good grinder and the stump is small (less than 4 inches), then you might have no problem at all. But if you have trouble removing larger ones, especially ones with deep roots, you may need to use an even bigger machine. You can get stump grinders with tree-shaped blades. This allows you to get as close as possible to the stump without causing problems.
But how close can you plant a tree to a stump if the tree is leaning on the ground? This depends on many factors, including how much the tree weighs and how far down the hole you are digging. But there's a simple solution for this - buy a staking machine. Stakes can move the tree in whatever direction you want them to go, and a grinder can grind the stump down to an acceptable level.
A bigger question is how close can you be to the stump if the tree is leaning more in one direction than another? A typical stump grinder has a rather large turning radius. If the tree is tilting more than its roots are spread out to, you might have a little trouble getting that tree to sit closer to the ground. But if you're willing to move the tree (and it's likely you'll have to) then a grinder can help. At least it will cut down some of the vertical distance.
One of the reasons why people have trouble trying to figure out how close can you plant a tree to a stump is that they try to work from the wrong side. Planting the stump forward usually helps, since you'll be facing the stump as you walk. And if you're not sure if the tree needs to be further forward, you can also use a hand to push it to the side. It should only take a few seconds to do this, and you won't damage the tree or hurt yourself if the tree is leaning too far out. And finally, keep in mind that you might not get as far as you think you did if you don't pay attention to the details when you're walking around.