Seaside Alder
Alnus maritima
- Native to:
- United States
Robert H. Mohlenbrock. USDA NRCS. 1995. Northeast wetland flora: Field office guide to plant species. Northeast National Technical Center, Chester, PA. Courtesy of USDA NRCS Wetland Science Institute.






Taxonomy
- Division:
- Magnoliophyta | - Flowering plants
- Family:
- Betulaceae
- Genus:
- Alnus
- Species:
- Alnus maritima
- USDA Symbol:
- ALMA7
Growth Characteristics
- Life Cycle:
- Perennial
- Growth Habit:
- Shrub , Tree
- Height:
- 1000 cm
- Light Requirements:
- Part Shade
- Drought Tolerance:
- Low
- Bloom Months:
- mar,apr
- Bloom Colors:
- yellow, brown
Wildlife Benefits
- Caterpillars:
- ★☆☆☆☆ Recorded caterpillar host plant (HOSTS Database)
Keystone Species Ranking
- Caterpillar Keystone:
- ★★★★★ Butterfly & moth species supported by this genus (NWF)
Host Plant for Caterpillars
Fall webworm (Hyphantria cunea)
Garden & Ecology Notes
- Wildlife Value:
- birds, small mammals
Soil Requirements
- Soil Type:
- moist, nutrient-rich, well-drained soil
- pH:
- 5.5 - 7.0 (slightly acidic to neutral)
- Drainage:
- tolerates poor drainage
- Moisture:
- consistently moist
- Notes:
- Often found in wetlands or near water bodies
Propagation & Germination
- Stratification:
- Cold/moist stratification required — 30–60 days
- Germination Time:
- 14–30 days
- Notes:
- Seeds require cold stratification for 30-60 days to break dormancy; sow in moist soil.
Pre-treatment: Cold-moist stratification for 30 days at 1–5°C (34–41°F).; then Cold-moist stratification for 60 days.
Source: Claude AI