Q: Two rows of tall Leyland cypress grow as a barrier between my house and a busy highway. Some of the lower limbs are dead. Can I cut fifteen feet off the top to make the remaining trunk bush out more?
A: Cutting the tops out of the Leyland cypress won’t do anything to make it bushy lower down. The plant will simply start making new vertical growth where you made the pruning cut. I think your only option is to plant thick green shrubs to hide the trunk. There are lots of evergreen shrubs to choose from: holly, cleyera, English laurel, etc