Incised Fumewort (Corydalis incisa) — identification, habitat & look-alikes

Incised fumewort is an East Asian plant with purple flowers that appears in damp eastern U.S. woodlands in early spring. Its leaves are deeply cut, and its tube-shaped flowers have a small pouch at the back. Incised fumewort contains toxic compounds and can form dense stands that crowd out native spring wildflowers.

Appearance

Growth form: A shade-tolerant and that grows under 2 ft (60 cm) tall. In its first year it forms a cluster of leaves close to the ground, then flowers in spring.
Leaves: Soft leaves split into threes, then threes again, with deeply toothed edges.
Flowers: Clusters of purple, tube-shaped flowers have a small spur at the back.
Flowering time: In Maryland, March through early May.
Fruit: Slim, pod-like capsules start releasing seeds about three weeks after the first flowers open.

Look-alikes

Yellow fumewortCorydalis flavula

Yellow fumewort (Corydalis flavula) has yellow flowers and less deeply cut leaves. Incised fumewort has purple flowers and leaves with deeper cuts.

Why they get mixed upBoth are low spring plants in eastern U.S. woodlands.

Where it lives

Typical habitats: Stream banks
Moist woodlands
Rock walls
Disturbed ground
Range: Native to Japan, Korea, Taiwan, and China. In the U.S. it has been reported from New York, Pennsylvania, Maryland, Virginia, and Washington, D.C., with reports also from North Carolina, Tennessee, and Illinois. In the eastern U.S., dense stands can crowd out native spring wildflowers.
Preferred conditions: Tolerates shade and does best in damp soil along rivers and in floodplain woods.
Flowering: Flowers Mar–May
Flowers Mar–May

Life cycle

Seed dispersal: Ripe pods burst when touched and fling seeds up to 10 ft (3 m). Ants carry seeds off for their fatty attachments, and water carries them even farther.

Cautions

Cautions: This plant contains toxic compounds.

Conservation

IUCN Red List: NENot EvaluatedNot yet assessed

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