Pseudotsuga Menziesii

Pseudotsuga menziesii, known as Douglas-fir (in the UK, 'Douglas fir' without the hyphen), Oregon pine, or Douglas spruce, is an evergreen conifer species native to western North America. One variety, coast Douglas-fir (Pseudotsuga menziesii var. menziesii), grows in the coastal regions, from west-central British Columbia, Canada southward to central California. In Oregon and Washington State its range is continuous from the Cascades crest west to the Pacific Coast Ranges and Pacific Ocean. In California, it is found in the Klamath and California Coast Ranges as far south as the Santa Lucia Mountains with a small stand as far south as the Purisima Hills, Santa Barbara County. In the Sierra Nevada it ranges as far south as the Yosemite region. It occurs from near sea level along the coast to 1,800 metres (5,900 ft) in the California Mountains. Further inland, coast Douglas-fir is replaced by another variety, Rocky Mountain or interior Douglas-fir (P. menziesii var. glauca). Interior Douglas-fir intergrades with coast Douglas-fir in the Cascades of northern Washington and southern British Columbia, and from there ranges northward to central British Columbia and southeastward to the Mexican border, becoming increasingly disjunct as latitude decreases and its altitudinal limits increase. Mexican Douglas-fir, which ranges as far south as Oaxaca, is often considered part of P. menziesii.

The specific epithet, menziesii, is after Archibald Menzies, a Scottish physician and rival naturalist to David Douglas. Menzies first documented the tree on Vancouver Island in 1791. Colloquially, the species is also known (incorrectly) as Douglas Pine or simply as Doug-fir.