Accession Count: 2
Common Name:
Japanese pagoda
Family Name:
Fabaceae
Botanical Name:
Styphnolobium japonicum
Sub Species:
Variety:
Forma:
Cultivar:
Characteristics:
The Chinese scholar tree is a medium to large deciduous tree that grows from 15—23 m (50—75 ft) tall, rarely to 30 m (~100 ft) (1, 2). It has a rounded crown that can be as wide as it is tall (2). Typically maintains a single, non-suckering trunk (4). Bark is gray-brown with deep furrows, which can appear reddish-brown (2). Stems remain green for the first four years of growth, before maturing to a copper-brown (2). Leaves are alternate, pinnately compound, to 25.5 cm (~10 in) long, with 7—17 leaflets which are 2.5—5 cm (1—2 in) long, oval to lanceolate, dark green, with margins entire (1, 2). Flowers bloom on 15.25—30.5 cm (6—12 in) long panicles in late summer (1, 2). Panicles can be as wide as they are long (1). The flowers are cream-white, small, pea-like, and fragrant (1, 2). Fruits are slender, knobby pods,called loments which are 7.6—20.3 cm (3—8 in) long and have from 1 to 6 seeds in each pod (1, 2). They appear bright green at first growth and mature to a yellow-brown (1, 2). Fruits constrict tightly between each seed, giving them a “beads-on-a-string” appearance, and remain on the tree through the winter (2). The seeds are poisonous and sour.
Compound:
Sty jap
Geographic Origin:
East Asia
Ecozone Origin:
Palearctic
Biome Origin:
Natural History:
Though this plant is often called the Japanese pagoda tree, it is native to China and Korea (1). It has been used as a decorative tree around Japanese Buddhist temples, where it garnered its English name (2). The tree has also been introduced to many other countries around the world, included Uzbekistan, Vietnam, Zimbabwe, and the United States (2). In its native Chinese and Korean habitats, the tree grows as dense thickets in highland forests and mountain slopes (2). It prefers full sun, though it can tolerate some shade (1, 2). It grows best in well-draining soils, specifically sandy, loamy soil (1, 2). The tree was originally included in the genus Sophora, but was placed into Styphnolobium because it lacks the ability to form symbiotic relationships with nitrogen fixing bacteria in its roots (a common trait among many Fabaceae genera) (3). The name Styphnolobium means “dense pods,” and japonicum refers to the misconception that the tree is native to Japan (1, 3). The species is not likely to be invasive in the Tucson area though it has been identified in the Mid-Atlantic Region of the United States as potentially invasive.
Cultivation Notes:
The Chinese scholar tree is quick-growing acharacteristic often desired in urban landscapes, though it was recently identified as an invasive in the Mid-Atlantic region of the United States (1, 2). It may struggle in hotter, more arid regions such as Tucson, since it is native to cooler, more mountainous regions with more consistent moisture (1, 2). The tree can handle full sun, but may need additional water in intense heat (1, 2). Seeds germinate best as soon as the fruits are ripe (4). If stored, pre-soak the seeds in hot (not boiling) water for 12 hours before planting (4). Plants do best when started in containers (4). After about two to three years, they can then be transplanted into the ground in early summer (4).The seedlings typically take at least 10 years before their first flowering (1, 2). The tree is well adapted to USDA hardiness zones 4a through 8b, becoming hardy with maturity (2, 4).
Ethnobotany:
This tree is well-known as being well-adapted to city life, specifically in its ability to tolerate pollutants and heat (1, 2). Additionally, its flowers and seedpods have a long history in Japan for their use for making yellow dye (2, 4). The fruits are poisonous, but the leaves and flowers are used medicinally (2, 4). The species is one of the 50 fundamental herbs in Chinese medicine, used as an antifertility agent, antibacterial, and hypotensive agent (4). The wood is used for construction and furniture (2).
Height:
50 - 100 feet
Width:
50 - 100 feet
Growth Rate:
Fast Growing
Grow Season:
Spring
Flower Season:
Summer
Color:
Cream
Function:
Shade
Spread:
Spreading
Allergen:
Non-allergenic
Invasive:
Benign
Toxicity:
Benign
Hardy:
Hardy
Water Use:
Moderate Water Use
