Appearance

Growth form

Upright, bushy plant usually about 3 ft (1 m) tall, sometimes up to about 6 ft (2 m), branching near the top.

Leaves

Feather-like compound leaves 8–10 in (20–25 cm) long, with many small hairy leaflets.

Flowers

Pea-like flowers, usually pale yellow to creamy white, in spikes 6–10 in (15–25 cm) long at the stem tips.

Flowering time

Early to late summer

Fruit

Slender pods that hang down, holding a few seeds each; fruits ripen from midsummer into fall.

Look-alikes

Japanese pagoda treeStyphnolobium japonicum

The pagoda tree is a large tree up to about 80 ft (25 m) tall that blooms in late summer, and its pods are pinched like a string of beads. Shrubby sophora is a knee- to waist-high plant.

Why they get mixed up · Both have creamy pea-like flowers and feather-like leaves, and they were once placed in the same genus.

Where it lives

Typical habitats

• Mountain slopes
• Sandy grasslands
• Shrubby thickets

Range

Native to China, Mongolia, Taiwan, Japan, Korea, and the Russian Far East, usually below about 4,900 ft (1,500 m). It is not native to the US.

Preferred conditions

Grows in open, sunny places such as grasslands, thickets, and field edges.

Growing it

Care

Rated hardy to USDA zone 6.

Toxicity

The root contains bitter alkaloids such as matrine. Taking the root can cause nausea, dizziness, and vomiting, and severe poisoning may lead to breathing failure.

Connected species

Caterpillar food plants

• Shijimiaeoides divina

  A rare East Asian blue butterfly of Korea and Japan whose caterpillars feed on this plant.

Conservation

IUCN Red List

LCLeast Concern·Low risk of extinction

Culture and stories

Culture and stories

• Its dried root, sold as ku shen ("bitter root"), is one of the classic herbs of traditional Chinese medicine and has also been used in Korea and Japan.