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The Douglas-fir is an evergreen tree, one of the 'tall pines' for which the Pacific Northwest region of North America is well known. It is the state tree of Oregon. As a forest, they are beautiful, but individually they cannot be called handsome trees. In natural environments, they grow close, tall and straight, up to 250 feet high, driven by the need reach above each other for sunlight. Their canopies are rather scraggly and they have long, droopy branches.

The Douglas-fir is not really a pine tree. Actually, it's not even fir tree, either, but rather a separate genus Pseudotsuga, so the common name is usually hyphenated as Douglas-fir to indicate that fact. The name honors David Douglas, the Scottish botanist who identified them in the Northwest in 1826. They are also called Oregon pine, British Columbian pine, Vancouver fir, red fir, and Douglas spruce among other mistaken names.

This confusion of names resulted from the confusion of early botanists, who had a difficult time of classifying these trees, as their characteristics crossed several boundaries of classification. In 1867, it was defined as a genus, Pseudotsuga, to distinguish it from the firs (Abies), pines (pinus), spruces and hemlocks. Of the six species of Pseudotsuga (which means false hemlock), only menziesii is native to the Northwest. Its growth range includes mainly southwestern Canada and the northwestern United States, but it also extends down through the Rocky Mountains as far as Mexico. It grows at altitudes from sea level to well over 10,000 feet.

One popular use for Pseudotsuga menziesii is as a Christmas tree. For that purpose, they are specially grown on farms, spaced far enough apart and trimmed so that they can develop a full, nicely-shaped canopy.

The wood from these trees is a major natural resource for North America and an important export. Most of the structural lumber used in wood-frame houses and elsewhere in the construction industry is either Douglas-fir or western larch. About two and a half billion Douglas-fir trees are planted every year. Although classified as a softwood, Douglas-fir is light, strong and tough.

It is also an attractive material for woodworkers. When quarter-sawn, it has an appealing straight grain figure and a warm, orangish-brown color in the heartwood, which contrasts strikingly with the creamy-white sapwood. It is fairly easy to work with, and stable, but you don't want to get a splinter stuck in your skin. The wood contains irritating oils and other chemicals that make splinters even more painful than usual.

Kingdom: Plantae, Division: Pinophyta, Class: Pinopsida, Order: Pinales, Family: Pinaceae, Genus: Pseudotsuga, Species: P. menziesii
The easiest way to tell that a tree is a Douglas-Fir is to look at its cones. If there aren't any on the tree, they're probably lying on the ground all around.

Underneath each of the scales of a Douglas-Fir cone is a funny-shaped lesser scale, known as a bract. Each bract has a long central stalk with a pointed wing on each side. Each bract strongly resembles a little mouse trying to escape into the cone. Pines, spruces, hemlocks and firs don't have these bracts; larches have wingless ones.

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If for some reason you can't find a cone to identify the tree, pull a needle off one of its branches. A Douglas-fir needle will have a small foot (called a petiole) at the base, and the branch will have a small raised area where the needle was. In contrast, if you pull a needle off a true fir, it will be the same thickness throughout and the branch will have a small depression.

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