Acer Triflorum
C. Dwayne Jones
Horticulturist - City of Waynesboro, Virginia
Parks&Rec@ci.waynesboro.va.us

For many horticulturists, scouring through new spring nursery catalogues in winter is an annual event. The first few pages reveal Abelia (glossy abelia) varieties, followed closely behind by Acer rubrum and its many fine cultivars. One maple I routinely search for, with very little success, is Acer triflorum (three-flowered maple). With a stunning fall display, incredible peeling bark and tolerance of various cultural conditions, why is this wonderful tree absent from most nursery catalogs?

A. triflorum is a common woodland tree in its native habitat of south central Korea and Manchuria. I have observed healthy specimens of the three-flowered maple in arboreta from Kirtland, OH to as far south as Raleigh, NC. Along with A. griseum (paperbark maple) and A. negundo (Boxelder maple), A. triflorum falls into a group of compound-leafed maples known as the trifoliate maples.

The slender pointed leaf buds emerge tiger striped, before the leaves fully expand to reveal a fine pubescence (right). As autumn approaches, the dark green leaves change slowly from soft yellow to a fiery orange-scarlet at its peak. According to Gary Koller, former senior horticulturist of the Arnold Arboretum of Harvard University in Jamaica Plain, MA, the annual color rivals that of the sugar maples of the New England landscape.

A. triflorum is certainly not a one-hit wonder with only spectacular fall color. The bark is perhaps its longest-playing hit. Throughout the seasons, the bark exfoliates vertically along older branches in a similar fashion as the Betula nigra (river birch). Beneath three flowered maple’s short, tannish-brown curls lies the light orange to almost white inner bark. Together they create a fantastic display that is especially effective in the winter landscape.                          

Three-flowered maple's small stature is another feature which contributes to its overall landscape effectiveness. Achieving an ultimate size of 20 - 30 feet tall with an equal spread, the tree grows equally as well in full sun as it does in almost full shade. In the open, the crown matures to form a dense round shape. As an understory tree, however, the internodes elongate, creating a more upright habit with a slightly thinner canopy. In addition to its tolerance of various light conditions, A. triflorum is quite adaptable to a wide range of soil types. Although it prefers acidic, moist, well-drained soil, three flowered maple is reported to prosper in soils with a higher pH. Outstanding insect and disease resistance round out its great cultural performance.

The absence of the three-flowered maple from nursery catalogs may be due in part to the difficulty in propagating it. Low seed viability combined with a double dormancy requirement of both warm and cold periods may discourage most nursery professionals from growing it. Treated, semi- hardwood cuttings taken in June exhibit moderate success, but continued experimentation may improve rooting percentages. Seedlings are available from specialty mail-order nurseries and may prove the simplest method to produce a salable plant.

As the size of landscapes continues to decrease, the popularity of small, tough trees such as A. triflorum will only increase. Low maintenance requirements, brilliant fall color and interesting peeling bark make three flowered maple an excellent choice for almost any landscape situation. Its merits have not gone completely unnoticed, as it was one of only four plants selected by the Pennsylvania Horticultural Society for it’s prestigious Gold Medal Plant Award in 1996. Why not help the search for great small trees, by incorporating Acer triflorum into your next garden design?

Botanical Name: Acer triflorum

Common name: three-flowered maple

Hardiness: Zone 5 - 7

Mature Height: 20 - 30 feet

Mature Spread: 20 - 30 feet

Landscape Use: Lawn specimen, small street tree, winter garden and mixed border

Ornamental Characteristics: Fiery, orange-scarlet fall color, peeling bark, small stature, and no insect or disease problems