Acer palmatum

Japanese maple, red emperor maple or palmate maple is in the soapberry or Sapindaceae family and is is a species of woody plant native to Japan, Korea, China, eastern Mongolia, and southeast Russia. It often grows as an understory, with multiple stems, and can reach a height of about 10 m.

Many cultivars of this maple have been grown throughout the world, often taking on a dome-like form when mature.

Three subspecies are recognized:

• Acer palmatum subsp. palmatum. Leaves small, 4–7 cm wide, with five or seven lobes and double-serrate margins; seed wings 10–15 mm. Lower altitudes throughout central and southern Japan (not Hokkaido).
• Acer palmatum subsp. amoenum. Leaves larger, 6–12 cm wide, with 7 or 9 lobes and single-serrate margins; seed wings 20–25 mm. Higher altitudes throughout Japan and South Korea.
• Acer palmatum subsp. matsumurae. Leaves larger, 6–12 cm wide, with 7 (rarely 5 or 9) lobes and double-serrate margins; seed wings 15–25 mm. Higher altitudes throughout Japan.

• Leaves are opposite, simple, up to 4–12 cm long and equally wide, palmately lobed with 7, 7 or 9 acutely pointed lobes. Fall color includes shades of yellow, red-purple and bronze.
• Flowers are produced in small cymes, individual flowers having 5 red or purple sepals and 5 whitish petals.
• Fruit is a pair of winged samaras, blunt-tipped and at about a right angle to each other, each samara 2–3 cm long with a 6–8 mm seed, maturing in late summer.