Also called cedar-apple rust, cedar gall rust results from the Gymnosporangium juniperi-virginianae fungus. Overwintering in infectious cedar tree galls, the fungus escapes to susceptible apple trees during wet spring weather. A few apple cultivars--including Jerseymac and Gala Supreme--are very resistant to the disease.
About this Author
A freelance writer, Judy Wolfe has owned Prose for the Pros, a freelance writing business, since 2006. She's been an inveterate traveler since 1961 and draws on her travel experiences to provide articles for such websites as Chincoteague Island Vacations and Berlin Dude. Wolfe holds a Bachelor of Arts in literature from California State University at Pomona.