Fusiform%20Rust (Cronartium%20fusiforme) - Fusiform%20rust%2C%20caused%20by%20the%20fungus%20Cronartium%20quercuum%20f.%20sp.%20fusiforme%2C%20is%20native%20to%20the%20southern%20United%20States.%0D%0ARust%20incidence%20varies%20greatly%20from%20site%20to%20site%2C%20with%20some%0D%0Astands%20being%20heavily%20impacted%20and%20other%20stands%20being%20rust%0D%0Afree.