New Search Printable Summary Slide Show Report Error

Scientific Name:
Alnus rubra
Pronunciation:
AL-nus ROO-bra
Common Name:
red alder
Family Name:
Betulaceae
Plant Type:
Tree - deciduous
Key ID Features:
Large red stalked buds; new stems angular; persistant woody cone; leaves have doubly serrate margins and are rolled under at the edges; male catkins are long and thin, hanging in clusters; female catkins short, thick, woody, held upright at the ends of branchlets. Winter ID: catkins persistent or immature; buds stalked, oblong, 10-14mm long; leaf scares raised, half-round to triangular with 3 bundle scars..

Habit:
Stiffly upright
Form:
Oval - vertical
Texture:
Medium
Mature Height:
22 - 30m
Mature Spread:
7 - 10m
Growth Rate:
Fast
Origin:
B.C. west of Cascades, U.S. - northwest, U.S. - southwest
Hardiness Rating:
Zone 3: (-40 to -34 °C)
Exposure:
Full sun
Soil/Growing Medium:
Acidic, Humus rich, Well-drained
Water Use:
Moderate
Landscape Uses:
Erosion control, Native planting, Tall background, Wetland - bogs, Woodland margin
Additional Info:

Leaf Morphology:
Form:
Simple
Arrangement:
Alternate
Texture/Venation:
Soft flexible, Heavily veined, Pinnate venation
Surfaces:
Glabrous, Lustrous
Colour in Fall:
Yellow, Brown
Shapes:
Ovate
Apices:
Acute
Bases:
Attenuate, Obtuse
Margins:
Double serrate

Inflorescence Type:
Catkin (ament)
Flower Morphology:
Monoecious plant
Number Of Petals:
0
Colour (petals):
Not showy, Yellow
Flower Scent:
None
Flower Time at Peak:
Mar, Apr, Aug

Fruit Type:
Samara
Fruit Colour:
Brown
Fruiting Time:
Aug, Sep, Oct
Additional Info:
Not showy, Persistent, Cone-like female catkin release many tiny samaras

Bark Morphology:
Smooth, Lightly fissured, Single stem trunk
Bark or Stem Colour:
Grey, Brown
Leaf Bud Type:
Oblong, Stalked
Leaf Scar Shape:
Half-round
Organ Modifications:
Ectomycorrhizae, Root nodules (N-fixing)
Propagation:
Seed, Greenwood cuttings, Hardwood cuttings
Maintenance:
Medium
Pest Susceptibility:
Beetles or weevils, Canker or sap rot, Caterpillar or cutworm, Fungal leaf spot, Galls, Root rot, Sawflies or horntails or ants (Pest resistant, Disease resistant)

Course(s):
  • AARB 1012
  • HORT 1155
  • Level 4 Apprenticeship
Location(s):
  • (FSC)  Far South Campus
Location Map