Identifying characteristics:
A wide-branching, highly ornamental tree with a rounded crown reaching a
height of 50 to 75 feet. The bright, lustrous green leaves
are pinnately compound, alternate and up to 1 foot long, with 7 to 17
ovate leaflets that remain neat and fresh-looking all through summer. The
leaflets are 1 to 2 inches long, have entire margins and hold their green
color late in the season, usually with little fall color. A clear yellow
fall color may, however, occur some years. This species is one of the last
of the larger trees to flower in the north-producing large, upright panicles
of mildly fragrant, creamy-white, pea-like flowers
from July to August. A snowy carpet of blooms usually adorns the ground
under the tree while it flowers. The fruit
is a rather ornamental, yellowish, chambered pod, 3 to 8 inches long, holding
3 to 6 seeds and strongly constricted between the seeds. Pods may persist
on the tree all through winter. The buds are concealed by the leaf
scar, with the base of the leaf stalk swollen to enclose each bud. The young
bark is pale gray, becoming furrowed
into fibrous, interlaced, scaly ridges.
Similar species:
Ecology:
Distribution: Native to China and Korea, and widely planted in Japan,
the Japanese pagoda tree was introduced to the US in 1747.
Habitat: This species is hardy to zone 4 and tolerant of many
soil types although it prefers loamy, well-drained soils. When young, this
tree may be susceptible to cold but can withstand heat and drought once
established. A medium to fast grower, it reaches a height of 10 to 12 feet.
in 5 to 6 years, but does not flower while young. Relatively free of pest
problems, this species may occasionally contract twig blight, powdery mildew
and canker.
Uses:
Wood: A yellow dye is made by simply baking the flowers until they
are brown, and then boiling them in water.
Horticulture: Sometimes also called the "scholar tree," it is frequently planted around Buddhist temples in the Orient. This valuable ornamental is not used in the urban landscape as often as it ought to be. It is tolerant of pollution and, because it casts a light shade, allows turf grasses to grow up to the trunk. Although the leaves, flowers, pods and rachises all fall at different times, Sophora japonica is not generally considered to be a messy tree as the leaves are smallish and the flowers rather attractive as they carpet the ground. Cultivars include 'Regent,' a fast-growing, young bloomer with abundant flowers and 'Pendula,' a small, weeping variety that seldom flowers.
