Japanese maple (Acer palmatum) is a small shrubby deciduous tree usually under 20’ tall (maximum 50’) typically with a very picturesque crown and contorted trunk and branches. Leaves are 3” long, deeply-lobed with 5-9 pointed and toothed lobes. While leaves are typically green, some cultivars have purple or red leaves and vary from relatively broad lobed and shallow sinuses to narrow and incised lobes divided at the base. Twigs are slender and reddish with tiny buds. Fruits are small with ¾” long wings that spread widely. Native to southwestern China, Korea, and Japan, no tree species has been more variable in cultivation. Japanese maple was reportedly introduced to England in 1820. A California nursery offered the species for sale by 1854. There are hundreds of garden cultivars of this species showing a wide range of color and leaf shape. The types include ‘Atropurpureum’ which has deep red –purple foliage which turns brilliant red in autumn. ‘Senkaki’, also known as the Coral Bark Maple which has small leaves maturing to orange-yellow and bronze in autumn; its leaves unfold in spring from slender buds and its winter shoots are bright pink. ‘Ribesifolium’ has currant-like leaves and is a small compact small plant of 16’ height. ‘Linearilobum Atropurpureum’ has spidery, red-purple leaves; its samaras are tinged red and hang in small clusters. This tree is a slow grower achieving in youth 10 – 15’ in a decade. Acer is the Latin name for maple trees
Common name: Japanese maple; Smooth Japanese Maple
Scientific Name (family and order): Acer palmatum Thunberg (Sapindaceae, Sapindales)
Species Origin: China, Japan , Korea
New Jersey Status: USDA Introduced
Habit: Small tree to large shrub. 10 – 25’ tall x 10 – 30’ wide; bole 8 – 12”.
Habitat: Zones 5 – 8. Found in thickets.
Trunk/Stem: Bark brown-gray smooth. Contorted trunk and branches. Leaves in horizontal layering.
Leaves: Deciduous, Simple, Opposite. Overall leaf pattern is round with a cordate base. Palmately-lobed, 5 – 7 deeply-divided, taper-pointed, double-serrated margin; 2-4” long and 4” across; bright green, smooth with tuft hairs in the vein axils beneath. Turning red-orange in autumn. Petiole is thin, glabrous, green or red and long (2”).
Flowers: Monoecious. Small red purple in upright to drooping stalked umbels of up to 20 individual flowers in spring as the leaves emerge. Red sepals and white petals.
Fruits and seeds: Joined pair of samara with green or red wings, 3/8”; obtuse angle. Pedicels may remain after the samaras shed.