Question
boxwoods have long brown raised ridges on branches that come off with a finger nail. Leaves are falling(a lot), in zone 5 MO/KS area

Answer
Hi Alex, It sounds like scale of some kind.  They suck on the plants or trees and weaken them.  You can use an insecticidal spray on your boxwood.  I would consider Atomic Grow which is organic and will restore your tree back to health so the bugs go elsewhere.  kathy