An Elm with browned leaves amongst green,

The characteristic leaf scorch of Dutch Elm

Names: Ophiostoma novo-ulmi, Ophiostoma ulmi, Dutch Elm Disease
Hosts: Elm (carried by Elm beetle, root sharing or unhygienic tree surgery)
Attacks: Stems and Branches
Consequences: Vascular collapse leading to death of the tree. Dutch Elm disease looks like burning or tree de-hydration. This is due to the tree blocking it’s own vascular system in an “allergic-reaction” immune response to the fungus.