With age, its bark darkens and exfoliates. *

A small- to medium-sized tree, trident fits nicely into a contemporary landscape. *

Acer buergerianum
An Asian maple with a Western future

Uncommon in the U.S. nursery trade, trident or three-toothed maple is widely grown in the Orient for garden, landscape and bonsai use. Native to eastern China, Acer buergerianum is commonly seen in Korea, Japan, Taiwan and China and could find a home in many Western landscapes.

It is well adapted to urban conditions, said to tolerate pollution, infertile soils, smoke, dust and some drought stress without leaf scorch. In Japan, it is planted as a street tree.

Trident is a medium to small tree, reaching 20-30 feet tall in a landscape, though specimens to 100 feet have been recorded in China. It is hardy to USDA Hardiness Zone 5 and performs best in acidic soils, else iron chlorosis may appear in its leaves. Carl Whitcomb of Stillwater, Okla., reports in his book "Know It and Grow It III" that trident may withstand alkaline soils and water with regular applications of elemental sulfur at a rate of 3 pounds per 100 square feet. In dry locations, he recommends protection from winds and leaf litter or mulch over its roots.

Fall is show time

Trident may be worth the trouble. In fall, its leaves turn from dark, glossy summer green to yellow, bronze, red or purple, likely depending on location. The selection Streetwise, introduced by Tree Introductions Inc. in Athens, Ga., becomes burgundy red. As the tree ages, its bark becomes scaly and defoliates, adding real winter interest.

Trident's leaves are distinctively three-lobed. The tree has a rounded growth habit and can be trained to a single stem or allowed to develop a multi-stem growth habit. Its size and shape might make it a good selection for outdoor living areas in contemporary, rather limited, landscapes.

While trident is nearly pest free, its bark can sunscald on the south side of the trunk if exposed to bright sun in the winter, so wrapping might be recommended the first few years. It is considered a somewhat slow-growing tree.

Lawyer Nursery in Olympia, Wash., propagates trident from seed stratified for 90 days at 36F, according to nursery manager Bob Buzzo.

-- David Morgan

SPECIFICS:
Name: Acer buergerianum
Common name: Trident or three-toothed maple.
Family: Aceraceae.
Description: Small- to medium-sized tree generally reaching about 30 feet tall. It has a distinctive leaf shape, lovely fall color and defoliating bark.
Landscape use: Best suited for well-drained soils of slightly acid pH and locations sheltered from drying winds. Should be considered for small landscapes, patios, container culture or under utility wires.
For more: Lawyer Nursery Inc., 7515 Meridian Road S.E., Olympia, WA 98513; (360) 456-1839; fax (360) 438-0344. Tree Introductions Inc., P.O. Box 5014, Athens, GA 30604; (706) 769-1202; fax (706) 769-4528.

* Photos by Michael Dirr

© 2000 Branch-Smith Publishing