See:
Juniper (Juniperus spp.) - Rust
Pear (Pyrus spp.) - Pacific Coast Pear Rust
Note Although several Gymnosporangium spp. cause rust diseases in the PNW on pear and crabapple, they are infrequently found on fruiting apples. Also, note that the species causing cedar-apple rust does not occur in the PNW.