ce·dar-ap·ple rust (sēdər-ăp′əl)
A disease caused by a rust fungus (Gymnosporangium juniperi-virginianae) that spends part of its life cycle on certain junipers, causing galls and twig dieback, and the remainder of its life cycle on susceptible apples or crabapples, causing yellow spots and early shedding of leaves or fruit.
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