The Oriental or Chinese arborvitae (Platycladus orientalis) is generally an oval large shrub/small conifer tree. The species is typically slow-growing and quite tolerant of adverse conditions. In contrast to pines, arborvitae keeps its lower foliage with age. The tree is typically multi-stem which makes them vulnerable to splitting apart in heavy snow. It has dense branchlets held vertically and nearly parallel in arrangement. Bark is thin, red-brown, separating into papery scales. Leaves scale-like, bright green but may turn brownish in winter. Cones are ovoid and fleshy, blue before they mature, scales thick and hooked. Also known as white cedar. This plant is also referred to as Biota orientalis L. The wingless seed distinguishes it from the other Thuja species. The name Platycladus comes from the Greek platys meaning “broad” and klados meaning a “branch”; referring to the two-ranked branchlets in the vertical plane. Specific epithet means “of the Orient.”
Common name: Oriental Arborvitae
Scientific Name (family and order): Platycladus orientalis (L.) or Thuja orientalis L. (Cupressaceae, Cupressales)
Species Origin: Korea, Manchuria, Northern and Western China. Introduced to the West before 1737.
New Jersey Status: USDA Unreported
Habit: A large shrub 18 – 25’ high x 10 – 15’ wide, dense, compact, conical or columnar when young with branches held vertically and becoming loose with age.
Habitat: Zone 6 – 11.
Leaves: Evergreen. Smaller than other species, distinctly grooved on the back. Those on the main axis about 1/12” long, triangular, ending in a blunt point, not pressed closely to the shoot; those on the finer sprays about 1/16” long, closely pressed, green on both surfaces. Branchlets arranged in a vertical plane. Leaf color bright yellow-green to grass-green in youth, changing to a darker green when older
Flowers: Monoecious, Solitary, Terminal. Cones fleshy glaucous green before ripening, ¾” long, 6 – 8 scales each with horn-like process or hook.
Fruits and seeds: Cones round to egg –shaped, ¾” long, fleshy , bluish green before ripening to brown; Scales usually 6, ovate, each with horn-like projection; 2 seeds per scale, ovoid about 1/8” diameter, wingless, This wingless seed distinguishes it from the other Thuja species which are winged.