Hazel Alder (Alnus serrulata (Aiton) Willd.)
Also known as smooth alder.
↑Summary
A shrubby, thicket-forming alder native to Eastern North America; the most southerly-occuring Alnus species on the east coast, and the only one extending into the deep south, although its range also extends northeast into Maine and Canada. Like most alders, this plant is a nitrogen fixer.
↑Range - Expand
| Legend | Color |
| Native | |
| Native or Not Present |
This tentative map is based on our own research. It may have limited data on Canada and/or Mexico, and there is some subjectivity in our assignment of plants as introduced vs. expanded. Read more in this blog post.
↑Habitat
Prefers full sun to part shade, wet conditions, and at least somewhat acidic soils. Found on shores of streams, rivers, and lakes, margins of swamps and other wetlands, especially where bog-like conditions exist. Prefers sites with low nitrogen availability, where its nitrogen fixation gives it an edge over other species.
↑Uses
Occasionally used as a landscaping plant, where it is valued for its showy catkins and for being generally easy to grow on sufficiently wet, sunny sites.
Also planted to restore wetlands, especially with degraded soils.
↑Related Plants
Closely related to and able to hybridize with Alnus glutinosa; hybrids are rare and resemble that species more than this one. Also hybridizes with A. incana.
Numerous Alnus species occur in North America, most native, although the introduced Alnus glutinosa also overlaps with this one in parts of its range. In much of its range, especially in the south, however, this is the only Alnus species.
Numerous other plants are in the Betulaceae (or Birch) family.
↑Links & External Resources
• Alnus serrulata (Brookside Alder) | Illinois Wildflowers (About This Site)
• Alnus serrulata (Hazel Alder) | USDA PLANTS Database (About This Site)
• Alnus serrulata | Go Botany (About This Site)
• Alnus serrulata (Hazel Alder) | Missouri Botanical Garden Plant Finder (About This Site)
• Hazel Alder | Virginia Tech Dendrology Factsheets (About This Site)
• Alnus serrulata | Biota of North America Project (BONAP) (About This Site)
• Alnus serrulata | NatureServe Explorer (About This Site)
• Alnus serrulata | Flora of North America (About This Site)
• Alnus serrulata | Missouri Plants (About This Site)
• Smooth Alder | Maryland Biodiversity Project (About This Site)
