This very hardy conifer, first documented at Nootka Sound, Vancouver Island, by Archibald Menzies (1754-1842), has several names, including Alaska-cedar and Yellow-Cedar, though it is neither yellow nor a cedar. Once placed in Chamaecyparis, it is now in the monotypic genus Callitropsis. In north-west Europe it is best known as a parent of Leyland Cypress.

It has a narrow natural range, always within 160km of the sea, along the Pacific coast of North America, running north from Oregon and Washington through British Columbia to Alaska, reaching 61°N in Prince William Sound. It usually grows in mixtures with other conifers, commonly Sitka Spruce.

Monoecious. Wind-pollinated female cones mature in two years, seeds wind-dispersed. Also reproduces vegetatively by layering, especially near the treeline where trees grow as krummholz or in bogs.

Moderately tall (35m), slow-growing and long-lived (700 years). Typically conical, with a very straight, deeply fluted trunk. Foliage of scale-leaves in flat sprays, green both sides, prickly when stroked towards the base, with a faint unpleasant mildew odour. Western Red Cedar differs: foliage not prickly, pleasant smell. Lawson’s Cypress differs: white markings beneath the foliage.

Prefers moist conditions, and well-suited to western regions of Europe. Hardy and shade-tolerant. Ornamental where introduced, with several cultivars available for foliage and tree form.

No notable associations where introduced.

Generally free of serious pests and pathogens.

Highly regarded durable timber, resists splitting, used in specialist construction, including marine piles, timber framing and boatbuilding.