some of our large box wood shrubs have turned yellow/gold on the tops and South sides

Question

We want to trim it away, is it OK to do it now?

Answer 1

Yes, but you must also treat the underlying problem, or you may lose the shrub with just pruning alone.

This article will help you to correct the issue: https://www.gardeningknowhow.com/ornamental/shrubs/boxwood/yellow-or-brown-boxwoods.htm