Thuja Plicata - Distribution and Habitat

Distribution and Habitat

Western Redcedar is native to the northwestern United States and southwestern Canada, from southeastern Alaska and British Columbia southeast through Washington and Oregon to the far northwest of California, primarily in coastal forests but with a disjunct inland population in the southeast of British Columbia, the extreme southwest of Alberta, northern Idaho and westernmost Montana. Pollen analysis and carbon-14 dating indicates postglacial colonization around the lower Fraser Valley around 6600 years ago. There it prospers and accounted for nearly half the vegetation in the area 500 years ago. Currently, Western Redcedar comprises about twenty percent of the region's forests.

Western Redcedar is among the most widespread trees in the Pacific Northwest, and is associated with Douglas-fir and western hemlock in most places where it grows. It is found at the elevation range of sea level to a maximum of 2290 m above sea level at Crater Lake in Oregon. In addition to growing in lush forests and mountainsides, Western Redcedar is also a riparian tree, and grows in many forested swamps and streambanks in its range. The tree is shade-tolerant, and able to reproduce under dense shade.

It has been introduced to other temperate zones, including western Europe, Australia (at least as far north as Sydney), New Zealand, the eastern United States (at least as far north as Central New York), and higher elevations of Hawaii.

The species is naturalized in Britain.