It makes a lot of difference what kind of tree you are doing, soil type, and so on. Many hardwoods will not
root at all, but the stored
energy in the bark will run up to the top and sprout leaves during spring, but with no root they will die. If you have a hardwood that is capable of growing on a cutting, and you put it in good soil with good moisture, you will get roots eventually. But it takes a long time.