Common Name: American arborvitae
Type: Needled evergreen
Family: Cupressaceae
Zone: 3 to 7
Height: 20.00 to 30.00 feet
Spread: 5.00 to 10.00 feet
Bloom Time: Non-flowering
Bloom Description: Non-flowering
Sun: Full sun to part shade
Water: Medium
Maintenance: Low
Suggested Use: Hedge
Leaf: Evergreen
Attracts: Birds
Other: Winter Interest
Tolerate: Clay Soil, Black Walnut, Air Pollution
Culture
Grow in average, medium moisture, well-drained soils in full sun to part shade. Somewhat wide range of soil tolerance, but prefers moist, neutral to alkaline, well-drained loams. Intolerant of dry conditions. Best in full sun, but generally appreciates some light afternoon shade in hot summer climates. Avoid full shade where foliage density will substantially decrease. Avoid exposed, windy sites.
Noteworthy Characteristics
Thuja occidentalis, commonly known as American arborvitae, Eastern arborvitae, Eastern white cedar or Northern white cedar, is a dense, conical to narrow-pyramidal (sometimes maturing to broad-pyramidal), often single-trunked, evergreen tree that is native to eastern and central Canada south to northern Illinois, Ohio and New York with scattered populations further south in the Appalachians to North Carolina. Mature trees may reach 40-60' tall in the wild over time, but in cultivation typically grow much smaller to 20-30' tall. Scale-like, aromatic, yellow-green to green foliage appears in flattened sprays. Red-brown bark will exfoliate on mature branches and trunks.
Genus name is the Greek name for a kind of juniper (Juniperus.)
Specific epithet means from the Western (Occidental) world.
The common name of arborvitae (tree of life) comes from early French settlers to North America who learned from Native Americans that the tree’s foliage could be used to treat scurvy.
‘Nigra’ is a conical cultivar that will grow to 20-30’ tall and to 5-10’ wide. It features flattened sprays of dark green foliage that retain good green color throughout the year including winter. Seed cones are not particularly showy.
Problems
Leaf blight may cause some foliage to spot and drop. Watch for canker. Leaf miner may damage leaf tips. Bagworms, mealybug, scales and spider mites are occasional visitors. Foliage may show some winter burn (turns yellow-brown) in exposed sites. Susceptible to damage/stem breakage in winter from ice and snow accumulations.
Uses
Foundations, screens and hedges. Specimen.