If you are searching for a tall evergreen conifer as a privacy screen, the four most popular in the Southern Appalachian region (USDA hardiness zones 6 and 7) are:

# 1 is Leyland cypress (x Cupressocyparis leylandii) which rapidly grows 40-50 feet tall and 20-25 feet wide in less than 25 years…if they live long enough. Leylands are mostly care-free the initial 10-12 years before an annual threat of fungus diseases arrives. They often grow too tall and wide in their space. Set leylands no closer than 18 feet apart at planting and require irrigation the first two summers if dry. There is little remedy for these diseases other than pruning on tall ladders.

# 2 is Japanese Cedar (Cryptomeria japonica), another fast grower, 30-40 feet tall and 20-25 feet wide after 30 years. Foliage tends to turn bronze colored over a cold winter (zone 6 and further north), but dark green needle color returns at the start of spring.

# 3 is ‘Green Giant’ arborvitae is a hybrid cross of (T. plicata), the west coast native arborvitae and Japanese arborvitae (T. standishi). Expect 25-30 feet height after 25 years. Species generally remains disease-free and rarely infested with bagworms. Native (non-hybrid) western arborvitae grows tall (50 feet) and narrow (15-20 feet) at maturity.

# 4 is Emerald® Eastern arborvitae (Thuja occidentalis), also called “Emerald Green”. It is semi-dwarf (slow grower), dark green compact shrub with narrow pyramidal form. Glossy bright green, flat sprays of scale-like needle foliage. This native arborvitae matures to 10 to 15 feet height and 4 to 5 feet width in 20-25 years.

All four conifers are hardy in zone 6. Eastern arborvitae is very hardy (zone 3), but not heat tolerant in the south (zone 8).