Acer carpinifolium

Hornbeam maple is in the soapberry or Sapindaceae family and is native to the main islands of Japan (except Hokkaido), growing in woodlands and along streams. It is a small tree, reaching up to 15 m in height.

• Branchlets are reddish-brown with lenticels.
• Leaves are deciduous, simple, opposite, 7–15 cm long and 3–6 across, with 18–24 pairs of parallel veins, serrated margin, resembling a hornbeam (Carpinus) (except maple leaves are opposite); autumn colour is yellow.
• Species is dioecious; flowers greenish yellow, 1 cm in diameter, on pendulous racemes 5-12 cm long, in spring as new leaves open.
• Winged samaras are double, 2–3 cm long, in strings linking many pairs (like the snakebark maples), spreading in 'coat hanger' shape (like Norway maple), maturing in late summer.
• Bark is gray, somewhat smooth, becoming a bit fissured with age.