Cedar apple rust is a foliar disease of apples. It has a two year cycle with two different host pants, red cedar and apples. Only apples grown in areas where red cedars exist are at risk of infection. Cedar apple rust overwinters on the red cedar in the form of large galls. In spring, finger like growths extend out of the galls, releasing spores during rainfall periods.
Apple leaves and fruit are infected with small yellow lesions. Lesions later turn to gold with small black dots on upper leaf surface. Cup like structures form on the underside of leaves and fruit later in the season.