Figure 1. Cedar-apple rust gall on eastern red cedar showing thoroughly wetted, gelatinous spore-bearing structures. (Alan R. Biggs, West Virginia University)
Cedar-apple rust is a fungus disease of apple and cedar and spends parts of its life cycle on each host. It is caused by Gymnosporangium juniperi-virginianae. The fungus can infect leaves and fruit of most cultivars in the eastern region. A notable exception is ‘Delicious’, which is nearly immune.
The most conspicuous symptoms on apple are bright orange, glistening …