Cuscuta japonica var. formosana
Japanese dodder
Photo: parent species Cuscuta japonica · (c) Nathan Aaron, some rights reserved (CC BY) · licence
Family: Convolvulaceae · Type: Perennial · Not Native
Cuscuta japonica var. formosana (Japanese dodder) is a non-native California perennial in the Convolvulaceae family, recognized by large conic fruits diagnostic.
Japanese dodder is a naturalized parasitic plant found in the Santa Clara Valley, Central California Coast, and spreading to other areas, typically growing on woody plants at elevations below 100 meters. Flowering from September to November, this plant produces small, cream-white flowers in dense spike-like clusters with 1 to 3 flowers per cluster. Growing as a thin, thread-like vine that parasitizes other plants, it lacks typical leaves and instead wraps itself around host plant stems. Its flowers are small, about 4 to 7 millimeters long, with a distinctive corolla tube featuring delicately fringed scales and triangular-ovate lobes. The fruit is a small, cone-shaped capsule 5 to 9 millimeters wide, containing 1 to 4 oblong seeds arranged in a puzzle-like cellular pattern.
Identification and appearance
Key characters: 15 sympatric species; large conic fruits diagnostic
Habitat and range
Habitat: Woody pls, e.g.,
Elevation: < 100 m
Outside California: Florida, South Carolina, Texas, native to Asia
Bloom period
Cuscuta japonica var. formosana blooms Sep-Nov.
How to tell it apart
vs Cassytha: Cassytha has green color visible on close inspection; Cuscuta is pure orange/yellow with no green.; vs Funastrum: Funastrum has leaves and grows from the ground; Cuscuta is leafless and grows on other plants.; vs Eriogonum: Eriogonum grows from soil with visible leaves; Cuscuta wraps around other plants with no leaves.; vs Epilobium: Epilobium has green leaves and stands upright; Cuscuta is leafless orange strings on host plants.; vs Brandegea: Brandegea has tendrils and leaves; Cuscuta has no leaves, just orange thread-like stems.
Frequently asked questions
Is Cuscuta japonica var. formosana native to California?
No. Cuscuta japonica var. formosana is not native to California (recorded as not native).
When does Cuscuta japonica var. formosana bloom?
Cuscuta japonica var. formosana blooms Sep-Nov.
What plant family does Cuscuta japonica var. formosana belong to?
Cuscuta japonica var. formosana is in the Convolvulaceae family, genus Cuscuta.
What habitat does Cuscuta japonica var. formosana grow in?
Cuscuta japonica var. formosana grows in Woody pls, e.g.,.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos
Last updated 2026-04-09
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.