I have a 13 year old, 50 ft tall Cherry tree. It has never been pruned. There are 5 large main limbs. Some as big around as 8 to 10 inches in diameter. All the leaves have dropped and it's December and around 35 degrees at night. Is now a good time to cut it and how far down the main shoots can I go? The 8 to 10 inches in diameter is approx half way up and where I want to cut it.
The late autumn and the beginning of winter are the best time to prune your tree. Spring is not recommended because many trees can bleed sap during that period. It's also not recommended to trim the main limbs, unless they are broken, sick and posing a danger. You should aim for the smaller dead branches and the ones which are already broken and dangling around. Young trees are easy to prune and maintain, but your cherry is already old, which makes the matter a little more complicated. Since the pruning would involve climbing on a ladder and making important choices, which will define your tree's health for the next year, I would recommend calling an expert company, which deals particularly with tree services. A licensed professional would be able to give you a guarantee and you can hold them liable if anything goes wrong.