Species of the Month: Douglas Fir & Other Conifers

Posted on Monday, Feb 2nd, 2015
Variety of Conifers


Trip: All trips in Idaho, Oregon, Washington and Montana.   


Habitat: Northwest Coniferous Forests

Likelihood of encountering this species: Guaranteed

Do you see the variety of textures and colors in these trees? I took this photo one damp North Idaho Spring day. I was inspired by this Panhandle Idaho forest blanketed on the mountainside  because there were so many different colors of green! I became interested in learning my trees from then on; how could I ignore such amazing variety any longer? 


As a beginner, learning the species of conifers is overwhelming, but I have some tips to help you. Conifers are trees with needles, not leaves. Generally, they are evergreens (they don't loose their leaves in the fall/winter), but a few do shed their needles every fall.


There are many types of conifers: firs, pines, larches, cedars, redwoods and junipers, just to name a few. I found that it is impossible to learn them all at once, especially when just beginning on tree-identification adventures. 


I recommend focusing on one tree a week. Learn what that tree looks like as far as its bark, needles, silhouette and cones. When you go on a walk, drive, or river float, see how many of this one species you can identify. Soon, you will become familiar with that tree and can move on to identifying a different one. 

Douglas Fir Pinecone


The Douglas Fir is an easy first conifer to identify. Common across the western United States, it occupies a wide range of elevations and habitats. 


The needles and cones of the Douglas Fir are fairly unique and easily distinguished from other conifers.


Starting with the needles, look for evenly spaced needles one to two inches long and arranged in a spiral along the twig. Collectively, the needles should look like a three dimensional pipe cleaner as opposed to a two dimensional feather. If the needles lay flat, this is the wrong tree. 


The cones on this tree are beautiful, about 2.5 to 5 inches long. It has a tear-drop shape with spiraling scales. Extending from underneath each scale is a thin forked flake. The picture here is  a classic example of the Douglas Fir needle and cone on a young tree. The cones are unique, there are no other species like it!


The Douglas Fir is named after David Douglas, a British explorer who traveled the Pacific Northwest shortly after the Lewis and Clark Expedition. He found the tree very unusual: it had characteristics of a fir, hemlock and pine. In fact, its genus, Pseudotsuga means “false hemlock.” But the Douglas Fir isn’t even a fir, it belongs to a genus of trees that are unique. There are three varieties in North America, four more in Asia, and that’s it.


Old Growth Douglas Fir

Many know the Douglas Fir as the Christmas Tree. Unfortunately, those folks who only know the Douglas Fir as a christmas tree do not get to appreciate it as a mature tree. Later in life, they are even more majestic! To the right, guests on a ROW Adventures Rogue River trip admire an old-growth Douglas Fir that survived a raging wild fire in 2005.


Douglas Firs are very useful as lumber. Because of their valuable status, many old-growth Douglas Firs have been cut down across the Northwest United States over the past two centuries by logging operations. Biologists used to think of these old forests were useless to the ecosystem, and that they were stagnant in producing new species and biological mass. Cutting down these old trees was viewed as a good thing.


However, modern scientists now know that old-growth Douglas Firs provide countless benefits to the ecosystem; they provide habitat and protection for birds, mammals, plants and fungi, recycle nutrients, release massive quantities of oxygen into the atmosphere, and fortify the forest against catastrophic fires. Old-growth Douglas Firs also help stabilize the ground, and reduce the impact of heavy snow and rains, leading to less land slides and flooding.


I hope you are inspired to learn about your conifers on your next adventure, wherever that may be!


I referenced most of my information at the following links: