{"slug":"thuja-occidentalis","scientific_name":"Thuja occidentalis","common_names":["Eastern white cedar","Northern white-cedar","Eastern arborvitae","Arborvitae"],"family":"Cupressaceae","type":"conifer","mature_height_m":15,"mature_spread_m":4,"growth_rate":"slow","lifespan_years":200,"hardiness_zones":[3,7],"sun":"full_partial","water":"medium","soil":"Moist, well-drained, neutral to alkaline clay or loam; natural home is limestone swamps and cliffs","native_range":"Southeastern Manitoba east through Ontario and Quebec to the Maritimes, and the northern United States from Minnesota to Maine with scattered populations south along the Appalachians.","description":"A dense, narrow, pyramidal evergreen with flat fan-like sprays of scale leaves, tiny cones and stringy reddish bark. It is the default hedge, screen and windbreak conifer across Canada and the northern states, with hundreds of cultivars from tight globes to narrow columns such as 'Smaragd' (Emerald Green), 'Techny' and 'Brandon'. Deer strip it in winter and heavy snow can split multi-stemmed plants; Ontario notes it does not tolerate road salt.","care":"Water regularly for the first two summers and in drought, and shelter from strong winter wind to limit browning. Shear hedges in early summer; tie up or knock snow off columnar forms. Protect from deer with fencing or repellents. Bagworm, arborvitae leafminer, spider mites and occasional cankers are the main problems.","benefits":["windbreak","birds","wildlife","flood_tolerant","small_space","long_lived"],"uses":["hedgerow","screening","windbreak","small_yard","timber"],"cautions":["toxic_parts"],"image_url":"https://upload.wikimedia.org/wikipedia/commons/a/a7/Thuja_occidentalis.jpg","image_credit":"Wikimedia Commons contributor, Public domain, via Wikimedia Commons","sources":["https://plants.ces.ncsu.edu/plants/thuja-occidentalis/","https://mortonarb.org/plant-and-protect/trees-and-plants/eastern-arborvitae/","https://plants.usda.gov/plant-profile/THOC2","https://en.wikipedia.org/wiki/Thuja_occidentalis","https://www.ontario.ca/page/eastern-white-cedar"],"data_note":null,"updated_at":"2026-11-08T01:00:46.205Z","page_url":"https://treerm.org/trees/thuja-occidentalis","markdown_url":"https://treerm.org/trees/thuja-occidentalis.md","regions":[{"country":"CA","region":null,"locality":null,"status":"native","note":"Native from southeastern Manitoba through Ontario and Quebec to New Brunswick, Nova Scotia and Prince Edward Island; grows throughout Ontario.","source_url":"https://plants.usda.gov/plant-profile/THOC2"},{"country":"US","region":null,"locality":null,"status":"native","note":"Native from Minnesota to Maine with scattered populations in the Appalachians south to Tennessee and North Carolina (more than 15 states).","source_url":"https://plants.usda.gov/plant-profile/THOC2"}],"license":"CC-BY-4.0"}