About Acer opalus Mill.
Acer opalus Mill. is a medium-sized deciduous tree that grows to 20 metres (66 ft) tall, with a trunk up to 1 m in diameter. Its leaves are glossy green, 7–13 centimetres (2.8–5.1 in) long and 5–16 centimetres (2.0–6.3 in) across, palmately lobed with blunt teeth, and turn yellow in autumn. The bark is grey and pinkish, and peels in square plates. It produces small yellow flowers that open before leaves appear. Its fruit is a pair of winged samaras, with each seed up to 1 centimetre (0.39 in) in diameter bearing a 1.5–2.5 centimetres (0.59–0.98 in) long wing. For distribution and habitat, this maple grows from sea level up to 2100 m above sea level. It can form small pure stands, or grow mixed with other broadleaved species including Quercus spp., Sorbus spp. and other Acer species. It prefers limestone soils, and grows successfully on both stony substrates and well-developed soils.
