These bushes produce berries on last years growth, so do I prune all the branches that grew berries THIS summer?
How and When to Prune Serviceberry Bushes
Certified GKH Gardening Expert
In cases like this you will prune new growth one year, and SOME of the old, the next. These will be pruned once a year, typically in winter. Here is an article that will help: https://www.gardeningknowhow.com/edible/fruits/serviceberries/growing-serviceberries.htm