Tree Diseases: Elytroderma Needle Cast

Introduction Elytroderma needle cast, also known as Elytroderma disease, is a fungal disease of pine trees. It is especially common on ponderosa pine. Elytroderma needle…

Tree Diseases: Annosum Root Rot

Introduction Annosum root rot, also referred to as annosus root rot, is a fungal disease of pine, spruce, and fir trees. The causal agent of…

Tree Diseases: Rhizosphaera Needle Cast

Introduction Rhizosphaera needle cast is a fungal disease that affects many spruce trees, particularly Colorado blue spruce, and Engelmann spruce. The causal agent of the…

Tree Diseases: Pine Wilt Disease

Introduction Pine wilt disease is an affliction of pine caused by the pine wood nematode, Bursaphelenchus xylophilus. The pine wood nematode is a microscopic parasite.…

Tree Diseases: Pine Needle Rust

Introduction Pine needle rust is a fungal disease that affects many species of pine. The disease is caused by over twenty species of Coleosporium fungi.…

Disease Profiles: Powdery Mildew

Introduction Powdery mildew is a fungal disease that affects a wide range of plants. It is caused by numerous fungi in the order Erysiphales, of…