General: Cypress family (Cupressaceae). Native shrub or tree growing to 15 (-38) meters tall, the crown narrowly conic to broadly pyramidal, with spreading, densely crowded branches; branchlets flattened, in fan-shaped sprays. Bark is gray to reddish-brown, 6-9 mm thick, fibrous, separated into flat, connected ridges. Leaves are evergreen, scale-like and abruptly pointed, 2 mm long, opposite in alternating pairs (in 4 rows), bright green above and pale green below, sometimes becoming yellow-brown in winter, with a spicy fragrance when crushed. Seed cones are ellipsoid, (6-)9-14 mm long, brown; seeds ca. 8 per cone, 4-7 mm long, with lateral wings about as wide as the body. The common name pertains to its northern distribution, cedar-like appearance, and white wood.

Variation within the species: ecotypic variation within the species has been documented but no naturally occurring variants have been formally recognized. Significant genetic variation has favored the artificial selection of many cultivars, which differ primarily in leaf color and growth habit.

Northern white cedar differs from western red-cedar (Thuja plicata) in leaf color (dull yellowish-green on both surfaces), minutely mucronate scales of the seed cones, and geography.

Distribution: The primary range of northern white-cedar is in eastern-southeastern Canada (west to Manitoba) and adjacent states of New England and the Great Lakes region (west to Minnesota); south of the main range, it occurs in scattered stands and southward along the Appalachians into North Carolina and Tennessee, where it is generally rare or extirpated. For current distribution, please consult the Plant Profile page for this species on the PLANTS Web site.