Image for Sitka Alder

Sitka Alder

Scientific name

Alnus sinuata


Sitka Alder is a hardy, fast growing, deciduous shrub species that typically grows between 3 and 4 m in height. This plant may also be known by the common name Wavy Leaf Alder or Slide Alder. The bark is smooth, thin, reddish brown to gray colored, and covered in lenticels. The leaves are alternately arranged, yellowish green colored with pale undersides, ovate shaped, and have doubly serrated margins. It produces long drooping catkins between April and June then seeds between July and august. The roots are useful for controlling erosion and stabilizing shorelines. The root system also contains nitrogen-fixing bacteria, converting atmospheric nitrogen into a usable form and increasing this nutrients availability in the soil, which can be beneficial for other nearby plant species. Additionally, this shrub produces a large amount of leaf litter to further improve the soil quality. This is a valuable species for re-vegetating riparian areas.

Planting conditions

Sitka Alder grows best in moist to wet conditions with full or partial sun exposure. It prefers poorly drained loam or clay soil types. It tolerates nutrient poor soil, periodically flooded areas, and steep slopes. This shrub can be naturally found in moist forests, around marshes and swamps, or along stream and lake shorelines.


  • Plant height:
    • Max 3m
    • Any
    • Over 3m
  • Moisture level:
    • Normal
    • Moist
    • Wet
    • Flood Tolerant
  • Light conditions:
    • Full sun
    • Partial sun
  • Soil type:
    • Sandy
    • Loamy
    • Clay
    • Rocky
  • pH:
    • Normal
  • Depth:
    • Potted
    • Bareroot
  • Plant type:
    • Shrub
  • Height:
    • 3-4 m
  • Spread:
    • 3 m