Alnus rubra

Red alder (Alnus rubra) is a fast-growing deciduous tree native to the Pacific Northwest, commonly found along streams, in moist lowland forests, and on disturbed sites. It can reach heights of 50–90 feet, with smooth, gray bark that becomes mottled with white lichens as it ages. Its serrated, oval leaves are green above and paler underneath, with small cones and catkins that appear in clusters. Red alder plays a vital ecological role by enriching soils through nitrogen fixation and stabilizing riverbanks. Its lightweight wood is used for furniture, cabinetry, and paper production, and it is a popular choice for smoking food due to its mild flavor.

Leaves

• 3–6 inches long

• Oval to ovoid with serrated edges

• Bright green above, paler and slightly hairy below

Bark

• Smooth and gray when young, developing white patches of lichen with age

• Thin and slightly fissured on older trees

Habitat

• Found in moist lowland forests, along streams, and on disturbed sites

• Thrives in nutrient-poor soils due to its nitrogen-fixing roots

Height

• Typically grows 50–90 feet tall

Age

• Lives up to 60–100 years, with rapid growth in its early decades