Acer rufinerve aka Grey Bud Snakebark Maple

Acer rufinerve is a deciduous tree from central and southern Japan. It belongs to the maple family, Sapindaceae. Common names include redvein maple, Honshu maple, and snakebark maple. In Japan, it grows on drier middle and upper forest slopes. Its name refers to rusty hairs beneath the leaf veins. The tree grows fast but has a relatively short life.

Garden trees reach about 30–40 feet [9–12 metres] tall. Oregon State gives a smaller range of 30–35 feet [9–11 metres]. The RHS reports a spread beyond 26 feet [8 metres]. It has an upright form and may grow several trunks. Young shoots have a pale, waxy coating. Young bark is smooth and olive green, with fine pale stripes. Older bark turns grey-green but keeps its light lengthwise lines. These stripes give bare trunks and branches interest in winter.

The simple leaves grow in pairs on the stems. Most have three lobes, though some have five. Their edges have uneven, double teeth. Leaves measure about 2.5–6 inches long and turn dark green in summer. The lower surface is paler, with reddish hairs along the veins. By late summer, hair tufts remain where the veins meet. Autumn brings yellow, gold, and scarlet shades. Greenish-yellow flowers stand in upright racemes after the leaves emerge. Chicago lists the bloom season as March to April. Paired winged fruits, called samaras, follow and mature in autumn. Each fruit has a rounded nutlet.

Grow this maple in sun or partial shade. It needs moist soil that drains well, rather than wet ground. Sources support a broad range of soils, including clay and sand. The RHS also lists loam, chalk, and all three pH classes. A sheltered site suits its growing needs. Listed hardiness spans USDA zones 5–7 and UK rating H5. The RHS gives 20–50 years to reach full size. Growers can raise new plants from seed or by grafting.

This tree can provide shade or serve as a specimen. It suits lawns, woodland gardens, Asian gardens, and naturalized areas. NC State reports no major problems, but the RHS lists possible pests. These include aphids, caterpillars, maple gall mites, and horse chestnut scale. Possible diseases include Verticillium wilt, maple leaf scorch, and honey fungus.