Birch and alder are two of the most common trees across North America and Europe. Both belong to the Betulaceae family of deciduous hardwood trees. But despite their similarities, some key differences between birch and alder are worth understanding.
In this in-depth comparison guide, we’ll explore everything you need to know about birch and alder trees – from their physical characteristics and habitat preferences to their wood properties and common uses. We’ll also look at specific examples like alder vs birch firewood, countertops, and more.
You’ll clearly understand how to tell these two tree species apart by the end. You’ll also know which suits different applications, from landscaping to woodworking.
A Brief Overview of Birch and Alder Trees
Let’s start with a quick introduction to each tree species.
Birches are deciduous hardwood trees known for their iconic white, papery bark. They are found across northern temperate regions, including North America, Europe, and Asia.
There are around 60 birch species, with some key types being paper, yellow, and European white birch. The wood is pale yellowish-brown in color.
Birch trees have an elegant, graceful appearance and are popular for landscaping. Their wood is used for firewood, timber, and making furniture, cabinets, and flooring. Birch bark was traditionally used for writing, handicrafts, and canoe building.
Alders are in the same Betulaceae family as birches. There are around 35 alder species, the most prominent being European and red alder. Alders are fast-growing trees that thrive in wet conditions along rivers and streams.
Unlike birch, alders have smooth grey-green bark that darkens as it matures. The wood has a reddish-brown tint. It is used for furniture, cabinets, paneling, and craft woodworking. Alder is known for its resonant properties and is a popular choice for electric guitar bodies.
So in summary, birches and alders share some similarities but have distinct characteristics. Now let’s explore those differences in more detail.
Comparing the Physical Characteristics of Birch and Alder
When seen up close, birch and alder have noticeable differences in their physical features. This includes the color and texture of the bark, the shape and color of leaves, tree size, and more. Knowing what to look for can help easily distinguish the two.
Bark and Leaves
One of the clearest ways to tell birch and alder trees apart is by looking at the bark.
- Birch trees have distinctive white, paper-like bark that peels off in horizontal strips. This papery bark is a hallmark of all birch species.
- Alder bark depends on the tree’s age. Young trees have smooth, grey-green bark. As the trees mature, the bark darkens and becomes scaly or loosely ridged in texture.
The leaves are another distinguishing feature:
- Birch leaves are oval or triangular, with doubly serrated edges and pointy tips. They are alternately arranged on branches.
- Alder leaves are more rounded without serrated edges. They have shallow lobes and toothed margins. The leaves have a toothed, wavy appearance.
Size and Height
In terms of height, birch trees are generally taller than most alder species.
- Depending on the species, birch trees can reach heights between 40 and 70 feet. Some types like yellow birch can grow up to 80 feet tall.
- Depending on the species, Alder trees have a wider range of mature height, anywhere from 16 to 98 feet tall. Most grow to heights of 40 to 60 feet.
So while birch skews taller, alder has a wider range of possible sizes. Specific growing conditions also impact height for both species.
Habitat Preferences: Where Birch and Alder Trees Grow Best
In addition to physical traits, birch and alder trees differ in their habitat preferences and growing conditions. Understanding where each species thrives can further help identify them.
Location and Climate
Birch and alder trees flourish in many of the same regions, including northeastern and western North America. But there are some key climate differences:
- Birch trees prefer cooler climates. They thrive in more northern regions of the U.S. and Canada. Birch can tolerate cold winters with temperatures below -40° F.
- Alder trees prefer temperate climates with mild winters. They flourish in wet soils along stream banks and are common in the Pacific Northwest. Alders can withstand winter temperatures down to -20° F.
Both birch and alder trees need sufficient rainfall and do poorly in drought conditions. Birch in particular requires moist soil.
Soil Texture Preferences
Soil type is another differentiator between birch and alder trees:
- Birch trees prefer slightly acidic, well-draining soil. The ideal soil texture is sandy, loamy, or silty with gravel content. Birch doesn’t do well in heavy, clay-like soil.
- Alder trees thrive in moist, coarse-textured soils that are gritty. The trees can tolerate poor drainage and compacted soil much better than birch.
The takeaway is that alder is better adapted to coarser soil compositions than birch.
USDA Hardiness Zones
The U.S. Department of Agriculture (USDA) planting zones indicate the climates where birch and alder trees grow best:
- Birch trees span USDA zones 2 through 9a, reflecting their preference for cooler climates. Birch thrives in zones 3 to 7.
- Alder trees cover USDA zones 2 through 11, indicating a wider climate adaptability. Alders grow well across zones 3 through 9.
So alders can tolerate warmer climates than birches, especially in southern planting zones. But both trees grow well across overlapping cool and temperate regions.
How Birch and Alder Trees Grow: Cultural and Biological Differences
Beyond physical traits and habitat, birch and alder also differ biologically in their growth. This includes root structures, nitrogen fixation, and sunlight needs.
Birch and alder feature distinct root structures:
- Birch trees have extensive horizontal root systems. The roots grow close to the soil surface and spread out mat-like.
- Alder trees have a taproot system with one primary vertical root. The trees also generate secondary feeder roots.
The shallow, spreading roots of birch make them prone to upheaval in high winds. Alder’s taproots provide greater stability.
Alder trees have a very unique ability among hardwoods – they can fix nitrogen from the air into the soil through a symbiotic relationship with bacteria in root nodules. This benefits surrounding plants.
Birch trees do not fix nitrogen. They rely on nitrogen availability in the soil.
This gives alders an advantage when growing in nutrient-poor soils. The added nitrogen also benefits nearby plants.
Sunlight and Shade Tolerance
Both birch and alder species can grow in full sun but also tolerate partial shade, with some caveats:
- Birch trees prefer full sun but can handle light shade. Growth slows in dense shade. Young trees need ample sun.
- Alder trees also grow best in full sun or minimal shade. Thick shade hinders growth, but mature trees tolerate it better than birch.
So both birch and alder can adapt to some shade, but you’ll get the fullest growth in full sunlight.
Wood Properties: Strength, Density, Workability, and Uses
One of the biggest differences between birch and alder lies in the properties of the wood itself. The color, density, grain patterns, and overall quality vary considerably between the two tree species. This makes each wood better suited for certain applications.
Wood Color and Grain
The wood of birch and alder trees has noticeably different coloring and grain patterns:
- Birch wood is pale yellow to reddish-brown with a fine, even texture. It has a straight grain with waves or curls.
- Alder wood has a light reddish-brown hue. It has a more irregular grain pattern with swirling knots and burls.
These distinguishing characteristics are visible in finished wood products.
Density and Workability
Birch and alder also differ in wood density, hardness, and ease of working:
- Birch wood has a medium density. It is lightweight and springy, which makes it easy to work with hand or power tools. The wood sands smoothly.
- Alder wood has a medium to high density. It is harder and denser than birch. The wood can be challenging to work because it tends to tear out. But it takes finishes very well.
So birch has a lighter weight and smoother working properties, while alder is harder to mill and sand.
The density also translates into differences in strength:
- Birch is moderately strong for a hardwood. It has good shock resistance but is low in overall hardness. Birch ranks 4 on the Janka hardness scale.
- Alder wood is very strong and rigid. It has excellent shock and impact resistance. Alder ranks 5 on the Janka hardness scale, making it harder than birch.
So alder’s higher density makes it the stronger and harder of the two woods. It is more resistant to dents and wear.
Decay and Rot Resistance
Neither birch or alder wood has strong natural decay resistance:
- Birch is susceptible to fungal infections and wood-boring insects. It has very little rot resistance.
- Alder is also prone to insect attacks. It has almost no resistance to decay fungi.
Without proper treatment, both woods perform poorly when exposed to the elements. They require preservative staining, painting, or pressure treatment when used outdoors.
Given the different wood properties, birch and alder lend themselves to some distinct uses:
- Birch is used for veneer, plywood, tongue and groove flooring, furniture, cabinets, trim, and turned items. It works well for smaller specialty wood objects that require intricate machining.
- Alder is used for furniture, cabinets, guitars, woodturning, and carving. It’s commonly seen in decorative veneers, paneling, doors, and millwork. Alder is a favorite for solid wood electric guitar bodies.
For larger structural pieces like beams and decking, alder has an advantage over birch due to its increased hardness and rot resistance. But birch is lighter and easier to machine for detailed crafts.
Next, we’ll compare examples like firewood, countertops, and lumber.
Birch vs. Alder: How Do They Compare for Specific Uses?
Now that we’ve covered the general differences between birch and alder trees, let’s drill down into some common uses to see how they stack up:
Birch vs. Alder Firewood
Both birch and alder provide good firewood, but there are some key differences in burning properties:
- Birch firewood burns hot and fast with fewer sparks. It has good heat output but doesn’t last as long. The wood seasons quickly.
- Alder burns slowly with a longer-lasting coal bed. It provides excellent heat output and produces fewer ashes. But alder takes longer to cure and season.
So birch firewood lights easily and offers a quick fire. Alder provides steady, even heating over a longer burn time.
Birch vs. Alder Countertops
Birch and alder are both used for specialty countertops. Here’s how they compare:
- Birch countertops have a uniform, attractive grain pattern. The wood is moisture-resistant but prone to dents and scratches. Frequent resealing is needed.
- Alder countertops have a bold, rustic grain. The wood is harder and more scratch-resistant. It holds up better to daily wear and tear. But alder is also more porous.
Alder has an edge over birch for countertops thanks to its hardness and scratch resistance. But birch costs less while still providing a pleasing aesthetic.
Birch vs. Alder Lumber
Both birch and alder lumber are used in construction for framing, siding, and trim:
- Birch lumber is lightweight, stable, and easy to work with. But it has low decay resistance unless pressure treated.
- Alder lumber is extremely durable outdoors. It has good stability but is more difficult to cut and join. Alder holds nails and screws well.
Alder’s natural decay resistance makes it a better choice for exterior uses. Birch requires chemical treatment to withstand the elements. But indoors, birch is easier to work with.
Birch vs. Alder Veneer
Birch and alder are both made into decorative wood veneers:
- Birch veneer has an attractive, uniform grain that stains well. It gives a pleasing “Scandinavian” aesthetic.
- Alder veneer has a lively grain pattern that looks bold and rustic. It adds visual interest to furniture and cabinetry.
For clean, light-colored projects, birch veneer is preferable. Where a dramatic look is desired, alder matches well with darker stains.
Yellow Birch vs. Red Alder
Let’s directly compare two specific species – yellow birch vs. red alder:
- Yellow birch is dense, strong, and heavy. It has a straight, close grain and resists splitting. Yellow birch costs more than red alder.
- Red alder has a more open, swirling grain pattern. It dents more easily than yellow birch but stains with greater uniformity. Red alder is also less expensive.
So for furniture or cabinetry, yellow birch has a strength advantage over red alder. But for stained projects, alder may provide better visual results.
Telling Birch and Alder Trees Apart: Identification Tips
Now that you know the differences between birch and alder trees, here are some tips for telling them apart when you come across them in nature:
- Check the bark – birch has white, papery bark while alder bark is smooth and greyish.
- Look at the leaf shape – birch leaves are triangular with serrated edges. Alder leaves are more rounded with shallow lobes.
- Consider the habitat – birches prefer cooler climates and drier, upland soils. Alders thrive in wet soils along streams and tolerates warmer areas.
- Examine the flowers and fruit – birch produces long, cylindrical catkins that droop down. Alder has clumped, oval catkins that stand upright on branches.
- Look up! Birch crowns tend to be pyramidal, while alder crowns are broad and oval.
With close inspection of these features, you can confidently tell birch and alder trees apart in the wild.
Birch or Alder: Which Tree is Better?
Now for the big question – if you had to choose between birch or alder, which is the better tree overall?
The answer depends on your specific needs:
- Graceful, elegant form with beautiful white bark
- Wood is lightweight, springy, and easy to work
- Burns fast and hot for firewood
- Ideal for furniture, turnings, crafts, and plywood
- Susceptible to pests and pathogens
- Wood has low decay resistance outdoors
- Not as hard or durable for countertops or flooring
- Fast growing and fixes nitrogen in soil
- Wood is very hard and durable
- Excellent for countertops, lumber, and high wear items
- Works well for resonance applications like guitars
- Bark isn’t as ornamentally attractive as birch
- Wood grain is more irregular and challenging to work
- Doesn’t season as quickly for firewood
For landscaping uses and ornamental beauty, birch is hard to surpass. But alder has a clear advantage for woodworking and construction applications where hardness matters.
Ultimately choosing between birch or alder comes down to assessing the characteristics that matter most for your specific needs and preferences. Either can be an excellent choice depending on the context.
Key Takeaways: How Birch and Alder Trees Differ
To recap, here are the main differences between birch and alder trees:
- Birch bark is white and papery; alder bark is grey-green and smooth
- Alder wood is harder, denser, and more difficult to work than birch
- Birch naturally grows taller; alder tolerates a wider range of climates
- Birch prefers drier, acidic soil; alder thrives in moist, coarse soil
- Birch has shallow, spreading roots; alder has a taproot system
- Alder can fix nitrogen; birch cannot
- Birch burns fast with a fire; alder burns slow and steady
- Birch works well for furniture and plywood; alder is better for heavy-wear uses
Despite being in the same plant family, birch and alder have distinct appearances, wood properties, and growing requirements. Being able to identify these key differences allows you to select the best species for your