The aspen tree grows extensively through the Rocky Mountains, especially in Colorado and Utah. Other than that, more aspen trees are found in Canada, than are found in the United States. The leaves of the aspen tree shake in the slightest breeze, earning the tree the moniker of “quaking aspen.” It is believed by scientists that all aspen trees in an area are actually part of one big organism, as the tree propagates by sending out shoots from the roots, spreading out underground and then breaking through in spots for new trees to grow, much like grass or bamboo spreads. This is unique amongst hardwood trees, which mostly propagate by the planting of nuts or seeds.
Some people mistake the aspen tree for the birch, which is similar in appearance. But the two trees are separate species. The wood of the two trees are very similar in appearance; both of them being some of the closest to white, with a fine, straight grain. In the case of aspen, there is very little differentiation between the coloration of heartwood and sapwood, making the boards relatively uniform in color throughout. While the bark is similar in appearance to birch, the leaves are different. The tree is also similar to the poplar, although once again, is a different species.
The aspen tree is fast growing, increasing in height by about two feet per year. Mature trees can reach as much as 100 feet in height, although 65 feet is more typical. A good sized tree will have a trunk two feet in diameter. It is fairly flexible, with an average amount of shrinkage while drying. The end grain reveals a very porous structure, which absorbs moisture easily.
Aspen wood is some of the softest hardwood there is, with a Janka hardness rating of only 420 lbs/ft. making it just barely harder than common pine sold in the stores. However, it has less knot than pine or common “whitewood” because of how the tree grows. Unlike conifers, aspen does not have branches growing out from the full length of the trunk. Poplar is slightly harder than aspen and birch is considerably harder.
Although not in as common use as many other woods, aspen is an inexpensive wood; inexpensive enough that it is occasionally used as construction lumber. For framing and other architectural applications, poplar has similar characteristics to other construction-grade lumber.
The most common use of aspen is as a core veneer for making hardwood plywood, especially if the mill making the plywood is near to areas where aspen are prolific. The fast growth rate and lack of demand for other purposes makes aspen an inexpensive wood. Aspen plywood is often on the inside of the cabinetry, where it does not have to bear a heavy load. The wood is also used for making boxes and crates.
Aspen is an easy wood to work with, although sharp tools are necessary to avoid creating a fuzzy surface. Generally speaking, working with aspen is very similar to working with pine. The same precautions to prevent splitting, tearout and chipping along the edges of pine, need to be used with aspen. The wood has a tendency to warp and twist during the drying process, so care should be taken when drying it. Fasteners, especially nails, do not hold well in aspen, due to the wood being so soft. However, it does glue well.
Aspen wood and plywood can be purchased through specialty lumberyards, especially those who specialize in selling hardwoods and hardwood plywood. The plywood can often be purchased through millwork shops which specialize in providing lumber to cabinetmakers. The cost of aspen boards and plywood are relatively low for hardwoods, similar to that of poplar.