Conifer trees - Douglas-fir

Plants and Trees


Pseudotsuga menziesii
Pine family
Where it Grows:

The inland variety of Douglas-fir is native to the mountains of the western United States and Canada. It grows in many kinds of forest - warm, low elevation forests as well as cooler, high Douglas-fir grows most abundantly in low to middle elevation forests. Douglas-fir will grow at high elevations on dry cool sites as well as lower elevations on warm dry sites. It can tolerate some shade, but grows slowly in a lot of shade.

What Douglas-fir Looks Like:

The leaves are needles and the seeds are in cones.
Leaves: The evergreen needles are between ¾-1” long. They are yellow-green with 2 white stripes on bottom of needle. The tips are rounded. The needles grow all around the twig like a bottle brush.
Cones: The light brown cones are 2-4 inches long with thin cone scales. The three lobed bracts that stick out between the cones scales make the cones distinctive-looking; the bracts look like a snake tongue or pitchfork.
Bark: Young trees have smooth, gray bark. As trees get older, the bark is more gray brown and gets very thick with deep ridges.

How Fire Affects Douglas-fir:

Young trees can be easily killed by fire. They have thin bark and low branches that can move surface fires up into tree tops. Older trees grow thick bark and can resist surface fires. However, fires in tree tops will kill them. Trees that survive may become so weak that bark beetles will attack.

Who Uses Douglas-fir?

People: Use Douglas-fir for products like plywood, construction lumber like 2x4s, railroad ties, and firewood. It is grown in farms for Christmas trees.

Americans Indians used the trees for wood, roots for baskets, and fresh needles for tea.

Wildlife: Provides valuable hiding places and food for bighorn sheep, deer and elk. Squirrels, mice and shrews eat the seeds. So do chickadees, nuthatches, and pine siskins. Blue grouse eat the needles.

What's in a Name?

The scientific name for Douglas-fir is Pseudotsuga menziesii. Pseudotsuga means "like a hemlock" When scientists first classified Douglas-fir, they thought is was a hemlock, but it wasn't. Later, they thought it was like a fir. But it isn't that either, hence the hyphen between Douglas and fir. The name Douglas comes from David Douglas a Scottish botanist who traveled the United States in the 1820s describing plants, including Douglas-fir.