If you want to get really specific, there are also some key similarities and differences between the way aspen and birch trees grow.
Differences Between Birch Trees & Aspens
Both birch and aspen trees have ornamental value in garden settings, and you can’t deny the beauty of a birch tree’s flaking bark or the glorious golden color of an aspen in autumn. The aspen tree is faster growing than a birch, but both species are used as shade or accent trees, and sometimes windbreaks in colder climate regions.
Taxonomy
Both of these trees are angiosperms, or flowering plants. However, they are classified into different plant families. Birch trees belong to the birch family, Betulaceae, whereas aspen trees are a member of the willow family, Salicaceae. Birch trees are then further grouped into their own genus, Betula. Aspen trees belong to the genus Populus, which makes them close kin to cottonwood and poplar trees.
- Both birch and aspen trees have ornamental value in garden settings, and you can’t deny the beauty of a birch tree’s flaking bark or the glorious golden color of an aspen in autumn.
- Birch trees belong to the birch family, Betulaceae, whereas aspen trees are a member of the willow family, Salicaceae.
Leaves
Birch leaves are generally medium to deep green and oval in shape with a tapering tip. The leaf margins, or edges are toothed. On the tree branch, the leaves are arranged alternately. Aspen leaves are glossy medium to dark green and are broadly oval with large, irregular teeth on the leaf margins, and lack any long, tapering tip as seen with birch leaves. Aspen leaves are arranged alternately on the branches. Both birch and aspen trees’ fall foliage color is yellow.
Both birch and aspen trees form a cluster of flowers called an inflorescence. The shape of the inflorescence is a catkin, sometimes called an ament. The catkin is a drooping cluster of tiny flowers that look like long strings or fingers and are usually wind-pollinated. Birch tree catkins are slender and appear in spring before leaves emerge. They are either male or female in gender, occurring on different branches on the same tree. Aspen trees’ catkins, a bit more robust in shape, also appear in spring before leaves appear, but male and female catkins appear on separate individual trees.
- Birch leaves are generally medium to deep green and oval in shape with a tapering tip.
- The catkin is a drooping cluster of tiny flowers that look like long strings or fingers and are usually wind-pollinated.
Do You Know Where You Are?
A really easy way to tell the difference between birch and aspen trees is to locate yourself on a map.
Aspen trees are found across most of North America, from Canada all the way down to Mexico, so that’s not necessarily going to narrow down your options. Birch trees, however, are generally only found in the eastern United States and parts of Canada. So, if you’re out West, the golden leaves waving at you probably belong to an aspen.
If you still aren’t sure after you’ve done some geography, then it’s time to get a closer look at the specific details of the tree.
Leaves Are Falling All Around
Take this chance to collect a fallen leaf or two; they’ll help you identify what kind of tree you’re looking at!
While the leaves of the aspen and birch trees look a little similar, there are several key differences. The white birch has a kind of spear-shaped leaf with a double-serrated edge, whereas the aspen leaf is more heart-shaped with small, rounded teeth. A longer leaf indicates a birch tree, while a stouter leaf belongs to an aspen.
Though helpful, this technique really only works if you have leaves to look at. If it’s winter time and the leaves have fallen, you’ll have to use other parts of the tree to determine whether the tree in question is an aspen or a birch.
Junk In The Trunk
If leaves are absent, take a look at the tree’s trunk. While their bark might seem the same from a distance, up close their color and markings can be used to tell the two apart.
The bark of the birch tree is truly white, while the aspen tree has a distinct green tint just beneath its whitish exterior.
The texture of the bark also drastically differs between the two types of tree. Birch bark will hang off the tree like pieces of paper, easily peeling away when pulled on. Aspen bark, on the other hand, will be tightly wrapped around the trunk.
In other words, if you can pull off the bark and use it for crafts like picture framing and decorative furniture, it’s a birch tree! In fact, birch has historically been used for basket making, canoe building, and even has distinct medicinal properties.
Additionally, both trees have different marks on their trunks. Aspens have knots that resemble eyes while birch have more horizontal markings all over the trunk. These markings are native to the plant and not necessarily a result of scarring from previous branches, which is often the case with aspen trees.
Between distinct leaf shapes and very different bark textures and markings, you should be able to easily tell the difference between a birch and aspen tree with a little up close examination.
