If you are looking to build something around your home, whether for a large construction project or a small woodworking piece, you have many different types of wood to choose from. Two common and popular choices include poplar and cottonwood.
That said, these are two fairly different materials, and today we are here to figure out what these differences are, and therefore which is best used for specific purposes.
What Is Poplar?
First, we have poplar, and here we are talking about the yellow poplar, as this is the most commonly found in North America, and one of the most commonly used for construction. That said, there are technically over 35 different types of poplar that can be found throughout the world, mainly in the Northern Hemisphere, particularly in North America, Northern Asia, and Northern Europe.
Although poplar is technically a type of hardwood, it is also one of the least dense and softest types of hardwood that can be found in North America. It also doesn’t contain too much resin or natural sap, which means that it’s not overly resistant to pests or moisture. This is definitely not a type of wood that you want to use for outdoor purposes.
The yellow poplar tree features a tight and uniform texture along with a straight grain, and it usually doesn’t have many voids, knots, or gaps. This wood features a creamy white or yellowish color and is mainly used for utilitarian purposes. It is popularly used for plywood, pallets, slabs, low-end furniture, and other low-end applications. It is a very affordable type of wood and it works well for indoor projects.
What Is Cottonwood?
We then have the cottonwood tree, and here we are talking specifically about black cottonwood. This tree can be found in northwestern North America, all the way up from Alaska down to the northern parts of Mexico.
The black cottonwood tree is technically a deciduous tree, and it is also a hardwood. Although, for a hardwood tree, it is actually extremely soft and lightweight, even more so than poplar. In fact, black cottonwood is by far one of the lightest and softest types of hardwood that can be found in the whole world.
This wood is not really pest or moisture-resistant, so it is not ideal for outdoor use. It is quite easy to work with, however, which is why many people prefer it.
The grain of black cottonwood is usually quite straight but may also be slightly irregular or interlocked, along with a medium texture. The heartwood is usually light brown with the sapwood being pale yellow. Black cottonwood is often used for utilitarian purposes such as plywood, veneer, creates, and boxes.
Poplar vs. Cottonwood: What Are the Differences?
Now that we know what both poplar and cottonwood are, let’s figure out what makes these two types of wood different from each other.
Hardness
Yellow poplar features a Janka hardness rating of 540 lbf, whereas black cottonwood comes in at just 350 lbf. As you can see, both of these types of wood are fairly soft in the grand scheme of things, with black cottonwood being much softer than yellow poplar. Neither of these types of wood is very resistant to denting or scratching, although cottonwood is even less so.
Density
Yellow poplar features a density of 29 lbs per cubic foot, while black cottonwood comes in at just 24 lbs per cubic foot. As you can see, yellow poplar is substantially heavier and denser than black cottonwood, which does lead to it being slightly more durable, although also a bit harder to work with as it can be difficult to maneuver.
Pest and Moisture Resistance
What needs to be said is that neither of these types of wood is very pest or moisture-resistant at all, with black cottonwood being even less so than yellow poplar. Even though yellow poplar is slightly more resistant to the elements than black cottonwood, it’s still not something that we recommend for outdoor use at all.
Overall Strength
What can also be said here is that although yellow poplar is not the most structurally sound type of wood around, it is much stronger and tougher than black cottonwood. If we are talking about things like compressive strength, the modulus of rupture, and the modulus of elasticity, poplar scores much higher on all of these fronts. However, both types of wood are still not ideal for weight-bearing applications.
Workability
Both of these types of wood are fairly easy to work with, although both can lead to fuzzy surfaces and edging when cutting, so very sharp blades need to be used. Yellow poplar is a bit heavier and harder, so it can be more difficult to work with in this sense, although black cottonwood has very poor nail-holding capabilities.
Appearance- Color and Grain
Black cottonwood may have a slightly more irregular grain than yellow poplar, and it also has a darker brown color than yellow poplar, which tends to be pale yellow or even creamy white. Both types of wood are fine for utilitarian purposes, and neither looks very special, although most would say that black cottonwood is the better-looking of the two.
Cost
Yellow poplar should cost you no more than $6 per board foot, and black cottonwood even less. Black cottonwood is generally considered to be a low-value type of lumber.
When to Use Poplar?
If you are planning on making some very low-end furniture, decorative pieces, boxes, crates, slabs, pallets, plywood, or veneer, then poplar is a perfectly fine option to go with. Just don’t use it for any weight-bearing applications or structural needs, and definitely do not use it outdoors.
When to Use Cottonwood?
About the exact same thing can be said for black cottonwood as for yellow poplar. It’s best used for utilitarian and low-end purposes, and should not be used for weight-bearing applications or for outdoor use.
Alternatives to Poplar and Cottonwood
If you need a type of wood that is more moisture-resistant and much stronger than both poplar and cottonwood, realistically, any other type of wood will serve you well. These can include various types of softwood such as pine and Douglas fir, or various types of hardwood such as oak, maple, teak, mahogany, and more.
Summary
As you can see, both black cottonwood and yellow poplar aren’t the strongest or most moisture-resistant types of wood around. However, a big advantage that they do have is being extremely affordable. If you just need some basic lumber for utilitarian needs, both of these types of wood are fine choices.