Our strata has several of these trees, about 5 years old and 8-10 feet tall. They have been generally healthy but this spring several have brown patches which I've also noticed on similar trees around town. There are no visible pests and no sign of webbing from spider mites. Does anyone know if this is caused by a disease, an insect or is just dieback from our bad winter? Can these plants be encouraged to regrow branchlets to replace the ones which died, or are the bare patches permanent?
