Alnus formosana

Formosan alder is in the birch or Betulaceae family and is native to Taiwan in China. It is a medium-sized tree, reaching up to 20 m tall.

• Leaves are alternate, simple, minutely toothed, elliptic or oblong-lanciolate, pointed, rounded base, 6–12 cm long and 2–5 cm across, hairy in the axils of lateral veins beneath.
• Species is monoecious. Male flower catkins are yellowish, up to 7.5 cm long, and in clusters of 3 to 5 at the branch tips; females are small, red, 1–2.5 cm long, ellipsoid, upright in clusters. They weather into brown woody (non-fragmenting) cones up to 2.5 cm long, in groups of 2 or 3.
• Bark is dark gray-brown, smooth, becoming fissured with age.