Orange Slimy Balls on Junipers? It's Cedar-Apple Rust

Those orange, gelatinous balls on your juniper are the spore-producing stage of cedar-apple rust (Gymnosporangium), a fungal disease. In year one, a brownish-green gall forms on juniper branches. The following spring, wet weather triggers orange "horns" that release spores infecting apple trees (the alternate host). Junipers (often called cedars) suffer minor twig dieback; apples can have seriously disfigured fruit and leaves.

The disease cannot spread juniper-to-juniper or apple-to-apple — it alternates. Break the cycle by planting apples and junipers far apart (difficult in suburbs). Or, pick off the green galls on junipers before they produce orange horns. On apples, the disease appears as orange spots; fruit is blemished but trees survive.