Douglas fir
evergreen conifer species
The Douglas fir (Pseudotsuga menziesii) is a conifer species in the pine family, Pinaceae. It is the tallest tree in the family. It is native to western North America and is also known as Douglas-fir, Douglas spruce, Oregon pine, and Columbian pine. There are three varieties: coast Douglas-fir (P. menziesii var. menziesii), Rocky Mountain Douglas-fir (P. menziesii var. glauca) and Mexican Douglas-fir (P. menziesii var. lindleyana).
Despite its common names, it is not a true fir (genus Abies), spruce (genus Picea), or pine (genus Pinus). It is also not a hemlock (genus Tsuga); the genus name Pseudotsuga means "false hemlock".
Description
Douglas-firs are medium-sized to extremely large trees, 20–100 metres (70–330 feet) tall (although only coast Douglas-firs reach heights near 100 m) and commonly reach 2.4 m (8 ft) in diameter, although trees with diameters of almost 5 m (16 ft) exist.
Begin with the source’s own compact description: “Douglas fir” is evergreen conifer species. The dossier treats that line as a proposition to test through Douglas, evergreen and conifer, not as a finished interpretation.
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The date and method of observation matter as much as the stated conclusion, especially where classification or consensus has changed. The source revision retrieved here is dated Sep 14, 2026. The linked authority identifier is Q156687. The Library of Congress control number is sh85039200. 1 of 1 selected statements include explicit references; 1 carry qualifiers and 0 use preferred rank.
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This entry incorporates text from “Douglas fir” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.