I have a black chokeberry shrub (that was identified thanks to this forum!) that is very overgrown. It's about 15 feet tall and very gangly. I just pruned about 1/4-1/3 of the biggest branches at the base - but it still is looking sad. I have read about doing a hard prune as low as 30 inches from the ground, however most of the branches don't have any offshoots or buds below that point. What is the best way to get this shrub under control without killing it?? Thank you!