The Borderline for Arborvitaes

Range

• Also called northern white cedar, T. occidentalis ranges from the Atlantic Ocean in the east to Canada’s James Bay in the north to Manitoba in the west to southern Michigan and New York to the south, according to the USDA Forest Service. T. plicata, or western red cedar, grows along the Pacific Coast from Humboldt County, Calif., northward to the southern tip of Alaska. Inland, the trees can be found in a strip from British Columbia south to Idaho and Montana.

Climate

• T. occidentalis’ northward spread is bounded by Canada’s subarctic region. To the south where the trees grow in the Great Lake states, the average yearly temperature is 60 degrees. These trees can be found in pockets even farther south – in areas of the Appalachian Mountains, for instance. Here the annual temperature averages 60 degrees. T. plicata trees that grow away from the coast withstand temperatures as low as 53 degrees below zero. Also, western red cedars grow in areas with a wide range of annual rainfall – from 28 inches to 260 inches.

Altitude

• T. occidentalis, which grows mostly between 500 and 2,000 feet, can be found as low as sea level, according to the USDA Forest Service. In British Columbia, T. plicata grows from sea level to 3,900 feet. Inland, western red cedars range from 1,050 feet to 7,000 feet. It grows at 7,500 feet along the edge of Crater Lake, Ore.

Asian Species

• Three arborvitae species grow in Asia. T. koraiensis can be found at mid altitudes in the Changbai Mountains, on the border between China and North Korea and possibly in South Korea, according to the International Union for Conservation and Nature and Natural Resources. T. standishii – which is native to southern Japan – grows in hardiness zone 5a, according to Sun Valley Garden Center. This zone has average annual low temperatures of 15 below to 20 below zero. The other species, T. sutchuenensis, is endangered and grows only in a small area of China.