About this tree
Thuja occidentalis, called northern white-cedar, eastern white-cedar, or arborvitae, is an evergreen conifer in the cypress family native to eastern Canada and much of the north central and northeastern United States. Usually a small to medium tree up to about 15 m tall, it has flat sprays of scale-like leaves and slender cones. The name arborvitae (“tree of life”) reflects historical beliefs in its medicinal value. It grows naturally in cool climates, often in wet forests and swamps, and can live for over a thousand years in protected sites. It is widely cultivated as an ornamental tree for hedges, screens, gardens, and parks, with over 300 cultivars including “Smaragd”, the variety found here at the Klostergut. Its wood has traditionally been used for fence posts and canoe planking. Indigenous Ojibwe culture honours it as “Nookomis Giizhik” (“grandmother cedar”) with sacred and practical uses. Although the foliage is rich in vitamin C and was reputed to help cure scurvy, it also contains high concentrations of the ketone thujone, which can cause seizures and death with prolonged internal use.