Speckled Alder
Alnus incana subsp. rugosa
Nitrogen-fixing pioneer species critical in wetland succession.
Field reference
Family
Betulaceae
Growth rate
Fast
Mature size
10–25 ft tall, 10–20 ft spread
Hardiness zone
2-6
Soil preference
Wet, acidic soils; bogs, swamps, stream edges
Sun
Full Sun to Partial Shade
Pruning window
Late winter
Wood properties
Soft, lightweight, low structural value; useful for erosion control plantings
Native range
Northern and northeastern North America
Green weight
45 lb/ft³
Common questions
Why is speckled alder important ecologically?
It fixes nitrogen in the soil and helps stabilize wetland and riparian ecosystems.
Where does speckled alder grow naturally?
It grows in wetlands, bogs, and stream edges across northern North America.
How fast does speckled alder grow?
It is a fast-growing pioneer species in wet soils.
Does speckled alder tolerate flooding?
Yes. It is highly tolerant of saturated and periodically flooded soils.
Is speckled alder useful for restoration?
Yes. It is widely used for wetland restoration and erosion control.
Related species in Betulaceae
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