If you get hit in the head with a piece of wood, you’re probably going to think it’s pretty hard. The bump will last for a while, too.
But, just how hard was the piece of wood that you got hit with? For that answer, you will need to know the species of wood and learn a little about the tree it comes from.
And here’s a new word for you today: dendrologist. In the field of botany, all plants are studied for their interaction with other plants and organisms and the environment in which they grow. Within the field of botany, there are specialists like dendrologists who specifically study trees.
A dendrologist would tell you to consult the Janka scale to determine that piece of wood’s hardness. A dendrologist would also tell you the technical name for aspen trees is populus grandidentata. This refers to the aspen species that prefer the Great Lakes States and New England for their habitat.
What is The Janka Scale?
The Janka test on wood, developed by Gabriel Janka, measures a wood’s resistance to denting. We don’t know if there is a corresponding test to measure your head’s resistance to denting, though.
The test answers the question, “How much force is necessary to embed an 11.28 mm steel ball halfway through the piece of wood being tested”? That force gives a rating on the wood’s hardness, and all woods are tested to determine that measure in available charts.
But, the Janka scale does not classify woods as either hardwoods or softwoods – only that pressure measurement with the steel ball. Whether a wood is a hardwood or a softwood is determined by other means.
What Are Hardwoods?
Hardwoods are woods that come from flowering plants known as angiosperms. We’ve written about them before, and you can find a detailed piece on our pages here when we wrote about pine. Examples of angiosperms are flowering trees like oak and walnut.
As a dendrologist can tell you, when you examine an angiosperm under a microscope, you will find the vessels that carry water throughout the tree, just as blood vessels carry blood throughout our bodies. They appear as pores.
Other examples of hardwood are beech, maple, teak, mahogany, and even balsa. Hardwoods are used in the making of high-end furniture and anything that needs to last. They also tend to be more expensive than softwoods and will have a slower growth rate.
What Are Softwoods?
Softwoods come from gymnosperm trees, evergreen conifers that make cones or needles. Their microscopic examination shows cell structure (tracheids) that will conduct water throughout the tree rather than vessels and show no pores.
Softwoods represent around 80% of all timber and are used in a wide variety of applications. For we woodworkers, that would include windows, doors, trim, and furniture, and for industry, paper.
Softwoods include pine, redwood, spruce, cedar, juniper, and yew. They tend to grow more rapidly than hardwoods and are less expensive.
What About Aspen Wood?
Aspen comprises much of the logging industry in Canada and south into the Great Lake states in the US. It grows rapidly in areas that have been deforested or burned down by fire and is in abundant supply as a result.
It’s widely used for a variety of purposes, and if you have picked your teeth lately, you might have had a piece of aspen in your mouth, as toothpicks are a common application for aspen wood. Beyond that, though, you’ll find it in furniture and wood paneling for walls. If you are a smoker and you lit your smoke with a wooden matchstick, it was likely an aspen wood matchstick, too.
While aspen wood is used for flooring, though, it might not be its best application. Flexible and beautiful, it’s not as durable or resilient as oak or maple, which remain better choices generally. It is also expensive, less resistant to moisture, and is easily a target of insect attacks.
However, in its defense, it is a stable wood, and its unusual color and patterns do make for an interesting and very different floor than that of oak or maple. It is also less susceptible to expansion and contraction from changing environmental conditions.
It’s a favorite food of beavers, who find its bark delectable in their diet. They also like to build their dams with its wood.
It’s also favored by grouse, but their interest is in the aspen seeds. They are tiny and easy to eat, and you need about 2 million of them to make up 1 lb. They are not commercially available as birdseed, though, where black oil sunflower seeds reign supreme in attracting the widest variety of birds to your backyard.
Aspens are related to cottonwood trees and willows. They grow rapidly, as we said, and in 20 – 30 years, can replace a harvested forest. They rarely top 60’, although they can exceed 90” on occasion, and are generally in the range of 20” diameter in size.
Older aspens will have a bark up to 2” thick and black near the base of the tree. Sapwood will comprise most of the wood with the white color of holly, while its heartwood will be more light brown in color.
For us woodworkers, we need to be aware that the wood of an aspen will tend to fuzz up when worked with, so you need to use very sharp blades for whatever saw you have chosen. However, aspen is a very stable wood, prized for it actually, and does not splinter. This makes it an excellent choice for children’s toy projects.
You’ll find no resin in aspen wood and is generally tough and stiff. It will resist splitting when nailed or screwed, and yet it is easy to work with using hand tools so long as the blade is sharp. It is also a good substitute for basswood (a common whittler’s and carver’s wood) as it is soft enough for the carving knife and strong hands.
It also glues well so long as you work quickly. While it takes paint well, it does not stain as well because it becomes blotchy. However, some find the absence of a true and visible grain pattern and color variation from white to light brown between sapwood and heartwood a desirable trait. More on that in the section about aspen wood flooring.
Aspen wood is odor-free and has no taste given to anything it comes in contact with, so it is suitable for bowls and baskets that might be used for food.
Qualities of Aspen Wood in Woodworking
For the right projects and uses, aspen wood can be a good choice. It is important to know its characteristics and qualities, though, to match it to the right projects. Here are some of the more important considerations when choosing your wood if aspen wood is on the list:
- Dense, but not too. At 25 lbs per cubic foot, it’s not as dense as red oak, for instance, another hardwood. This makes it among the lightest of hardwoods.
- Stability. Once dry, aspen wood is pretty stable and does not shrink much as inner moisture evaporates.
- Gluing. It takes glue well. However, it’s an absorbent wood, so you will want to apply pressure quickly when gluing. Have your clamps handy and ready to go.
- Strength. It’s about half as strong as red oak, another hardwood. If you use aspen wood in furniture making, use it in lightly used furniture that doesn’t need to be especially strong. For that, oak and maple are still better choices. However, in its defense, aspen wood does take nails and screws well near edges and will tend not to split. It’s strong enough to use as studs in home construction and in making pallets. In use as a flooring wood, it will show dents, dings, and scratches, though.
- Grain. The rings of aspen wood are very close and not easily seen. The color is mostly light (the white of holly, light brown otherwise), and it is difficult to separate the sapwood (outer) and heartwood (inner core).
Aspen As A Hardwood
As we have already indicated, aspen is a hardwood. However, as hardwoods go, it’s pretty soft.
We’ve mentioned the Janka test to determine a wood’s hardness. We thought it would be helpful to show its test score in comparison to other woods.
| Wood | Janka Score |
|---|---|
| Basswood | 410 |
| Aspen | 420 |
| White Pine | 420 |
| Douglas Fir | 660 |
| Mahogany | 800 |
| Cedar | 900 |
| Walnut | 1010 |
| African Mahogany | 1100 |
| Birch | 1260 |
| Red Oak | 1290 |
| Lignum Vitae | 4400 |
As you will note from the chart, aspen wood ranks very low on the scale of hardwoods, making it one of the softest of hardwoods. We even included a softwood, Southern Yellow Pine, to show you the extent to which aspen wood is the softest hardwood that even a softwood is harder than in Janka testing.
Aspen Wood Flooring – An Alternative to Consider
Aspen thrives in the cold and moderately cold environment of North America and does so because of its stability rather than its hardness. It is because of that stability, its resistance to expansion and contraction due to changing environmental conditions of moisture and temperature that floor installers will consider aspen wood floors.
Its unusual color variations from almost white to light brown, coupled with a grain that is barely discernible, can offer a different floor experience than the more traditional oak, maple, or cherry. Each of those latter hardwoods ranks much higher for hardness on the Janka scale, and their grain patterns are prized in homes.
Yet there is an appeal to the alternative aspen wood appearance, something different and out of the ordinary, that can appeal to those looking for something different.
We mention this simply in fairness to present different views in the marketplace and in real world woodworking experiences. While we’ve seen aspen wood floors in photographs and not in person, there is an offbeat charm to its appearance in a room.
The Craftsman View of Aspen Wood
We’ve noted that aspen wood is an alternative to basswood in the hands of carvers and craftsmen, and we even noted basswood on the Janka chart above as an even softer wood.
The basswood tree is, in fact, a hardwood just a bit softer than aspen wood. It was used by the indigenous North American people to make ropes, rugs, and bandages. It’s common to North America, and especially New England.
Because aspens also grow in the same areas as basswood, it too became popular with wood carvers, whittlers, and craftsmen. As noted earlier, it does not splinter and is soft enough with a carving knife and strong hands to shape well into spoons, bowls, animal and bird figures, and more. It is favored for carved figures and toys for children, again safe in their hands without splintering.
We’ve given you a lot of information about aspen trees and their wood, but there is more. We found a very informative video, only a few minutes long, that presents a lot more interesting facts about it, and you might enjoy watching.
We’ve never worked with aspen wood before, and the material in this article was based upon research from a number of authoritative sources rather than from woodworker websites. We’re in the northern US and aspen does grow here, right along with basswood (the carver’s favorite), and we did find out the local lumberyard can source it for us if we decide to use it. We’ve become curious enough to consider it for a project later in the year, even if it is just a carved spoon
You’ve learned about aspen wood and perhaps even learned a new word: dendrologist, a scientist that studies trees. To be honest, that was a new word for us, too.
So if you’re going to get hit in the head with a piece of hardwood, you could do worse than with a piece of aspen wood.