Aspen trees are pretty well-known for some great characteristics in home landscapes.
In fact, you might find you’re not sure what this tree is more loved for – its brilliant yellow foliage in autumn, its whitish trunks that stand in bold contrast, or the rustling of its quaking leaves.
On top of that, the quaking aspen is a widely distributed native North American tree, growing in diverse environments.
Think you have an aspen in your yard or maybe want to add one? Here are some aspen tree facts and types of aspen trees you can try to get the visually appealing contrast they bring to your landscape.
How To Identify An Aspen Tree
The aspen tree has quite a few identifying features that can help distinguish it from other trees.
You might notice its tall, slender appearance, for instance. Also, if you see them in forests, aspens tend to grow in groves rather than as single trees. Aspens often reproduce vegetatively, meaning they send up above-ground shoots from their below-ground roots. So sometimes a single grove of multiple trees is actually clones of the same organism!
The quaking aspen tree is the most common species of aspen growing in North America. They grow between 20 to 80 feet tall and 20 feet wide.
But the leaves and bark of aspens are also quite unique.
Aspen Tree Leaves
Aspen tree leaves are flat and round with pointed tips and serrated edges.
The leaves make a soft, fluttering sound, and even in gentle breezes, the leaves flutter showcasing shiny upper leaves with duller undersides, resembling butterflies.
Aspen Tree Bark
The long, slender whitish trunk of the aspen tree stands out with its black marks, showcasing a distinguished pattern.
The trunk is slender, and the aspen tree bark is thin. At the base of the tree, the bark is coarse, gray, and furrowed, getting smoother and lighter moving up the tree.
Aspen Tree vs. Birch Tree
Aspen and birch trees can be confused quite a bit. In fact, some people will mistake them for the same tree. But they do have some distinct differences.
Certain birch species are well-known for having bark that peels back, similar to paper. Aspen tree bark, on the other hand, does not peel.
Another differentiating characteristic are the leaves. Aspen leaves are flat, wider, and rounder, while birch leaves are slightly V-shaped and more elongated.
Aspen Tree General Characteristics
- Grow zones: Aspen trees grow well in USDA hardiness zones 2 to 8.
- Where to plant: Plant this tree in rich, well-drained soil that can be consistently moist. Avoid planting aspens near buildings since they tend to have a vigorous, invasive root system.
- Height/spread: The aspen tree grows between 20 to 80 feet tall and 20 feet wide.
- Sunlight: This tree grows best in full sun.
- Flowering dates: Aspen catkins elongate before the leaves expand. Catkins appear in mid-March to April with flowering in May to June.
- Best time to prune: Winter – outside of an aspen tree’s active growth cycle – is the best time for pruning.
- Deer resistance: Deer do like to seek shade in aspen groves in summer, and they also can consume the bark, leaves, buds, and twigs throughout the year.
Types Of Aspen Trees
These are the most popular types of aspen trees.
- Quaking Aspen (Populus tremuloides)- Also known as trembling aspen, quaking aspen trees are the most popular. They get their name from how they appear to flutter or tremble on windy days – even in light winds. These aspens have round leaves instead of pointed ones. Reaching a height of 65 to 80 feet, the quaking aspen has smooth, greenish-white to gray bark with wide black horizontal marks and dense black knots. The leaves turn yellow in the fall. Grow this tree in USDA Hardiness Zones 2 to 6.
- Bigtooth Aspen (Populus grandidentata)- This aspen species is found in northeastern and north-central U.S. It gets its name from the larger teeth on its leaves compared to other aspen species. The bark on these aspen is thin, olive-green, and smooth when young, turning gray, thick and rough with knots and grooves as it ages. This tree, which grows in USDA Hardiness Zones 3 to 6, likes sandy soils.
- European Aspen (Populus tremula)- This aspen tree species is one of the most spotted as it stretches beyond the U.S. from the Arctic to northern Africa and from Western Europe to Japan. Similar to quaking aspen, this tree also has round, fluttering leaves with curvy margins. Coppery hues in spring turn green in summer and then yellow in autumn. Grow this tree in USDA Hardiness Zones 2 to 8.
- Chinese Aspen (Populus adenopoda)- This aspen species originates from China, hence its name. It has smooth, grayish-white bark and smooth leaves. In China, this tree tends to grow in more mountainous regions. Grow this tree in USDA Hardiness Zones 5-10.
- Korean Aspen (Populus davidiana)- Native to Asia, this aspen tree has green, round or orb-shaped leaves with pointed tips and smooth, grayish-white bark. The lush foliage enhances a rounded crown that can grow up to 80 feet tall. Leaves turn golden yellow in the fall.
Some of the biggest threats to aspen are wood and bark boring insects. During their larval stages is when these insects cause the most damage. They are attracted to wounded or weak trees.
Spongy moth caterpillars (formerly gypsy moth) are also a threat to aspen trees. In April or early May, these insects begin feeding on new leaves. Weak trees are more susceptible to these pests, so fertilizing regularly and eliminating stress may help keep your trees strong.
To keep potential threats from harming your aspen trees, maintain a proper watering schedule since these trees don’t like over- or under-watering. Also, avoid wounding the main trunk with the lawn mower or other equipment, which can attract boring insects.
NEED HELP IDENTIFYING WHAT TYPE OF TREE YOU HAVE? CONTACT YOUR LOCAL ARBORIST FOR A FREE TREE INSPECTION!