red alder
Betulaceae (Birch family)
Introduction to Vascular Plants
Species Information
General:
Deciduous shrub or tree, up to 25 m tall; axillary buds with stalks; bark scaly, often lichen-covered, yellowish-brown or grey-splotched with white.
Leaves:
Alternate, deciduous, smooth, coarsely to irregularly toothed, the teeth pointing outwards, leaf margins rolled under, brownish in the fall.
Flowers:
Inflorescence of male and female catkins which open before the leaves enlarge; male catkins with stalks.
Fruits:
Small nutlets, with narrow-winged margins; female cones 1.5-2.5 cm long, egg-shaped.
Illustration
If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.
Illustration Source: The Illustrated Flora of British Columbia
USDA Species Characteristics
Flower Colour:
Red
Blooming Period:
Early Spring
Fruit/Seed characteristics:
Colour: Brown
Present from Fall to Spring
Source: The USDA
Ecology
The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)
| Site Information |
Value / Class |
||
|
Avg |
Min |
Max |
|
| Elevation
(metres) |
128 | 0 | 1700 |
| Slope
Gradient (%) |
12 | 0 | 150 |
|
Aspect (degrees) |
167 | 0 | 360 |
| Soil
Moisture Regime (SMR) [0 - very xeric; 4 - mesic; 8 - hydric] |
5 | 0 | 8 |
| Modal
Nutrient Regime
Class |
D | ||
| #
of field plots species was recorded in: |
1590 | ||
| Modal
BEC Zone Class |
CWH | ||
|
All BEC Zones (# of stations/zone) species was recorded in |
BWBS(1), CDF(151), CWH(1265), ICH(9), IDF(7), MH(4), SBS(1), SWB(1) | ||
|
Source:
Klinkenberg 2013
|
|||
Habitat and Range
Moist woodlands, forests, floodplains and clearcuts in the lowland and montane zones; common in coastal BC; N to SE AK and S to CA.Status Information
Synonyms
Synonyms and Alternate Names:
Alnus oregona Nutt.
Alnus oregona var. pinnatisecta Starker
Taxonomic Keys
1. Leaves finely once or twice saw-toothed; axillary buds unstalked, pointed; male catkins unstalked; stalks as long as or longer than the conelike sillicles..........................A. viridis
1. Leaves coarsely to irregularly round-toothed; axillary buds pedunculate, blunt or short-pointed; male catkins stalked; stalks shorter than the conelike silicles 2. Leaf margins rolled under; nutlets with narrow-winged margins.......................................A. rubra 2. Leaf margins not rolled under; nutlets wingless..................................A. incana Source: Illustrated Flora of British Columbia, Volume 2 |
Taxonomic Notes
Cut-leaf Red Alder
Red alder is probably the most common deciduous tree in the southern part of British Columbia. The leaves normally have shallow, rounded teeth along their margins. The leaves of the cut-leaf mutant form have irregular, sharply pointed teeth and lobes, thus resembling some black oak leaves more than alder leaves. Source: Extracted with permission from Griffiths and Ganders, 1983. Flowering Period This species flowers in the first week in March in the Fraser Delta. |