Firewoods Local to Durango and La Plata County – Which are Best?

US Highway 550 as it cuts through the San Juan National Forest, in this photo partially made of golden autumn aspens and naked ones, near Castle Rock

While any good camping trip typically involves just snagging whatever sticks and logs you can find near your site, building a fire in your home’s wood stove requires a little more care.

This is because all wood was not created equally. Different types of wood produce different BTUs. BTU stands for “British thermal unit” and, according to the EIA, is defined as:

One BTU is the quantity of heat required to raise the temperature of one pound of liquid water by 1° Fahrenheit (F) at the temperature that water has its greatest density (approximately 39° F).

The higher the BTUs, the hotter the fire. One BTU is roughly equivalent to the amount of heat created by burning a single match.

Skip the descriptions, to a list of all firewood types, along with their BTUs, in order of highest to lowest.

Let’s look at the different types of trees native to our area, and their BTUs. Fun with fire! (Without the danger, of course.)

Hardwoods Native to La Plata County

The forests surrounding Durango, Colorado are primarily coniferous. This means they consist of trees that have cones, and typically these are evergreens, such as you’d imagine using for a Christmas tree. Which, in turn, means we don’t have a plethora of hardwoods.

Hardwoods almost always have higher BTUs than softwoods, so the fact that we have fewer varieties of them is a bit of a bummer. Still, one of the most abundant trees in the area, our seemingly unlimited aspen groves, are a hardwood. But does that mean they’re good for toasting up your cabin all winter long?

Let’s compare our local hardwoods.

Note: BTU listings below are in millions. So a listing of 16 BTUs below actually means 16,000,000 BTUs. While this terminology is not scientifically accurate, it’s how many normal folks will refer these numbers, and just makes it easier to display the info below. Numbers are approximated from various sources across the web, listed at the bottom of this article.

Quaking Aspen

Populus tremuloides
BTUs: 18

The tall, white-barked trees with “eyes” — actually the remnants of fallen limbs — and small, bright green, almost heart-shaped leaves which turn brilliant yellow in the fall. The ones growing in our region are specifically called Quaking aspens.

Considered a “low BTU” wood, aspen is better suited for starting fires than long, hot burns.

Gambel Oak

Quercus gambelii
BTUs: 30

This hearty oak is abundant in our region, but barely grows larger than a shrub. In lower elevations, or where given more decades to grow, it may be up to 20 feet high. Gambels don’t tend to grow thicker than a few inches, and so can be cut into usable logs that don’t need to be split. They’re great for tiny wood stoves, but given their extremely high BTUs, make for the best logs in our area for wood stoves in general.

Cottonwood

Populus deltoides and Populus angustifolia
BTUs: 15

You’ll find cottonwoods growing along rivers and other very wet areas. Their trunks are often massive, if only at the bottom, and they tend to branch out into many, smaller trunks quickly. We have two types of cottonwoods in our area, Plains cottonwood — which have leaves similar to those of aspens, but much larger — and Narrowleaf cottonwoods, a variety with long, slender leaves reminiscent of smaller willows.

Cottonwoods, to an even greater degree than aspens, serve better as the beginnings of a fire than what you might want for the bulk of your long-lasting winter stash.

Softwoods Native to La Plata County

Ponderosa Pine

Pinus ponderosa
BTUs: 17.5

While many a layman will refer to any coniferous tree as a pine, “Pondo” is the most abundant — and nearly only — actual pine tree in our area. Distinguished by its orange bark that tends to look like parts of a jigsaw puzzle, it grows throughout our area, and seems to do just about equally well at higher elevations as in the deserts. If you purchase wood from a local supplier, it will quite often be pondo you’ll be stacking in your woodshed.

If this is the case, then you’re not much better off than just using aspen. Many folks in the area will swear by ponderosa pine, though, and given its long history of use, it has proven that availability is often more important than the quality of a wood when it comes to keeping your toes toasty this winter.

Bristlecone Pine

Pinus aristata
BTUs: 16

In parts of Utah and California, a species of Bristlecone pine live to be the oldest organisms on our planet, some over 4000 years old! Here in the San Juan Mountains, though, bristlecones are a fairly unremarkable species that grow more quickly and into a more traditional pine. In fact, if you didn’t look carefully at their needles — which resemble a bottle brush and its bristles, hence the name — you might think you’re just looking at another Ponderosa pine.

Relatively rare, unless you fell one yourself you won’t likely be burning much bristlecone this year.

Douglas-fir

Pseudotsuga menziesii
BTUs: 23

An abundant tree in our area, “Doug-fir” is probably the second most likely tree you’ll find should you purchase wood in the area, after Ponderosa pine. Dark grey, furrowed bark and a rounded shape to larger trees, the easiest way to distinguish a Dougie from other conifers is to look for the “mouse tails” on its cones. Ranking #3 based on BTUs and given its plentitude, Douglas-fir is probably the all around best wood one can hope for in our area.

Fun fact, Doug-firs grow to enormous, redwood-sized trees in the Pacific Northwest, and while they’re a slightly different species, some historical reports seem to indicate that they were actually — given an absence of mankind’s logging — the tallest trees on the planet.

Piñon Pine

Pinus edulis
BTUs: 27

Second only to Gamble oak as far as BTUs go, piñon pine (also spelled pinyon) tends to, in my experience, contain a lot of sap. Along with juniper, it is found in our region’s southern deserts. A combination of juniper and pinyon are common if you purchase your wood from places like Mancos or Ignacio (where wood is more abundant if, say, you ran out halfway through the winter.)

Its shape tends to make it want to fracture, as opposed to split easily. Pinyon pines, in general, are the source of commercial pine nuts.

Rocky Mountain Juniper

Juniperus scopulorum
BTUs: 22

Not to be confused with the very small shrub growing along our mountainsides, called Common juniper, the Rocky Mountain variety actually grows into a relatively short tree, in what are known as Juniper/Pinyon forests.

Juniper tends to light easily, thanks to the “strands” of almost hair-like bark that tend to hang from it, and also burns wonderfully hot. It also has a lovely fragrance, and you’ll often hear people refer to it as cedar in La Plata County. It’s personally harder for me to source, but aside from Gambel oak, is my wood of choice.

White Fir

Abies concolor
BTUs: 16.5

Perhaps the second most abundant conifer, after Douglas-fir, white fir — along with all of the true firs and spruce in our area — is one of the fastest burning woods with the lowest heat output. Never one to turn down free firewood, I’d pass on white fir unless someone dropped a truckload of it off for free.

White fir can be identified by long, upward curving needles that are a much lighter shade of white beneath than above, and an almost silver bark. They are the most “Christmas-tree shaped” even when fully mature.

Note: “True fir” refers to trees that are actually in that family, as opposed to the hyphenated Douglas-fir, which is actually a species all of its own.

Blue Spruce

Picea pungens
BTUs: 15.5

Also known as Colorado spruce, this is our state tree. The name comes from the almost blue color of the needles, especially when young. I don’t personally find these spruce to be common in our mountains, but they do tend to line many parks and streets. Low IBUs and the potentially for Coloradan sacrilege make it a less than ideal tree for firewood, but the perfect specimen to capture all of Santa’s presents.

Englemann Spruce

Picea engelmannii
BTUs: 15

Much more abundant, but even lower in quality, than the Blue spruce, I don’t have much experience burning Englemanns en masse. Most easily identified by their orange bark and “Dr. Seuss”-esque limbs, which droop down before climbing skyward again at their ends, both Englemann and Blue spruce have very similar cones, only visually differing in size.

List of Firewood Types Native to La Plata County, by BTUs

Gamble Oak
BTUs: 30
Piñon Pine
BTUs: 27
Douglas-fir
BTUs: 23
Rocky Mountain Juniper
BTUs: 22
Aspen
BTUs: 18

Ponderosa Pine
BTUs: 17.5
White Fir
BTUs: 16.5
Bristlecone Pine
BTUs: 16
Cottonwood
BTUs: 16
Blue Spruce
BTUs: 15.5
Englemann Spruce
BTUs: 15 

Of course, there are many more trees in our area. Smaller native trees like alders and Rocky Mountain maple don’t tend to grow large enough for anything other than kindling, while non-native trees aren’t conducive to gathering cords of wood. You may see massive weeping willows up and down US 550, but the likelihood you’ll fell one and buck it up before its owner has the police dragging you away is slim.

Sources

BTU information is largely an average of information available from World Forest Industries, Firewood Resource, and Utah State University.