Re: Red Twig Dogwood Die-back
It sounds to me like it might be twig blight (canker). This can be controlled through cultural practices: Carefully clean up dead leaves in the fall so that the disease cannot overwinter. When removing the diseased branches dispose of them rather than compost. Pruning twig dogwoods properly will make a difference in controlling twig blight. There are two methods for pruning twig dogwoods, Rejuvenation every 3 years or thinning by 1/3 every year, cutting out the oldest wood. Margaret follows the rejuvenation method. For more details and illustrations about both methods check out this CO State fact sheet, page 5 for thinning and pages 5 & 6 for rejuvenation. Regardless of which method you decide to adopt later, I would try a rejuvenation pruning now to see if you can save the shrubs. Since the fungus can travel on the blades of your pruners, make sure that you disinfect them between cuts!