Thuja occidentalis 'Spiralis' is a slender, narrowly upright selection of eastern arborvitae with spirally twisted branches and foliage. These traits distinguish this form from all other arborvitae. Foliage is dark- to medium-gray-green in color. After 10 years of growth, a mature specimen will measure 6 feet (2 m) tall and 32 inches (80 cm) wide, an annual growth rate of 6 to 8 inches (15 - 20 cm).
This cultivar originated as a seedling selected in the U.S. back in the 1920s. The name is thought to have been first published in 1920 by Alfred Rehder in Bibliography of Cultivated Tree and Shrubs; and introduced to the nursery trade by Bobbink & Atkins Nursery, New Rutherford. NJ
