I recently wired a juniper (the common kind you get at the nursery) about a
month ago. It's a cascade style; the ends are doing fine, but closer to the
trunk I'm getting dead spots.

Where are you keeping it? If you are in the Northern Hemisphere, it should be
dormant.
Iris,
Central NY, Zone 5a, Sunset Zone 40
"A tree never hits an automobile except in self defense." - Woody Allen