I have a weeping pussy willow tree. This is it's second year. It is growing very well. My question is that I don't know how to prune it. Last year I just cut off about 2 feet of branches all around so that it wasn't touching the ground. But I think that is not the proper thing to do. Can someone help me with this. In the middle of the tree is also quite a lot of dead branches. Do I take these out also? Thanks so much.