Answer: Actually, early spring is the best time to prune junipers and picea. Mid-summer pruning will stress the plants and also expose what were inner branches to strong summer sunshine. Since the growth was shaded and protected by the branches and leaves that were pruned off, the exposed foliage is unable to tolerate the sun. I'd leave the plants alone for now and then next March or April prune off the damaged foliage.
Best wishes with your garden!
Q&A Library Searching Tips