I planted 75 Black Locust trees that I purchased from the conservation district. They were about 2' when i planted them last spring and they are currently about 4' tall. I would like these to grow fairly straight with minimal low branches. Should i be pruning them and cutting off extra leaders now? Should I maintain these like any other tree or is there special considerations to take? Is the consensus that pruning should be done after a freeze or in the winter? I plan on planting 75 more next spring for future firewood production. I am kind of putting all of my eggs in one basket? Should i maybe plant a different species in case my Locusts get a borer or some disease. Thanks in advance.