Alnus sieboldiana

Alnus sieboldiana (オオバヤシャブシ in Japanese) is in the birch or Betulaceae family and is found in Japan, on the main islands of Honshū and Shikoku, and on the smaller Suwanose Island. It is a large shrub or tree that can reach up to 12 m or more in height.

• Branchlets stout, glabrous, yellowish to greyish brown; buds have 2 glabrous, membranous bracts.
• Leaves are deciduous, 6–10 cm long and 3–6 cm across, ovate to deltoid, upper surface green, lower surface pale green, 12–15 lateral veins on each side of the midvein, with appressed pubescence on veins; margins are doubly serrated with mucronate teeth, apex is acute to shortly acuminate; petiole is glabrous, 1–1.5 cm long.
• Male flowers are catkins 4.5–9 cm long; female flowers are solitary, pedunculate, ellipsoid, 2.4–2.8 cm long and 0.6–0.8 cm across, flowering from March to June.
• Fruit is a woody cone 2.5–3 cm long and 1.5–2 cm across, with bracts of 0.5–0.6 cm wide; ripening is from September to October in Japan.