Needles Don’t Grow Back: Rhizosphaera Needle Cast and Your Trees

Plant Nutrition, Tree Care, Tree Diseases

What is Rhizosphaera Needle Cast? Rhizosphaera needle cast is a fungal disease caused by the pathogen Rhizosphaera kalkhoffii, which most commonly affects Colorado blue spruce trees. This disease results in premature needle loss, particularly in the inner and lower canopy of the tree. Left untreated, Rhizosphaera needle cast can cause significant damage, including complete defoliation…