
Junipers will not resprout from old bare wood, so any cut made past the green foliage leaves a dead stub permanently — shearing a red cedar is a one-way decision and topping one to reduce height never recovers. Work it in late winter to early spring before growth pushes, and reduce by cutting back to a live lateral inside the green rather than heading the whole outline.
True decline here is site-driven — standing water in stripped-topsoil lots, or concrete poured over the root plate — and shows as whole-branch flagging, where an entire limb browns at once rather than the crown thinning evenly. Interior needle browning and shed each fall is normal seasonal drop, and rust galls are cosmetic to the cedar itself; bagworm is the one that actually kills, because a branch stripped bare by bagworms will never refoliate.