Seasonal Needle Drop of Arborvitae, Pine and Leyland Cypress
Several people contacted me in November 2021 and sent pictures of the brown needles in their arborvitae and Leyland cypress. What I noticed is the brown needles were on the inside of their trees, not on the outside. The outside of the plants looked green and healthy.
From this, I conclude this is normal needle drop. Pine trees and other needled evergreens do it too. I know it looks serious, but the evergreen will grow new foliage in spring and all will be well.