Apium nodiflorum
European marshwort
(c) Cliff, some rights reserved (CC BY) · licence
Family: Apiaceae · Type: Herb · Not Native
Apium nodiflorum (European marshwort) is a non-native California herb in the Apiaceae family, recognized by key differences are stem rooting at nodes and narrower leaflet shape.
European marshwort is a naturalized perennial found in the central Coast Ranges around Albany and eastern San Francisco Bay in wet places at elevations generally below 1,000 meters. Flowering from May to August, this plant produces small white flowers in delicate umbrella-like clusters with 10 to 20 unequal rays. Growing 1.5 to 10 decimeters tall with stems that root at lower nodes, it spreads easily in moist environments. Its compound leaves feature oblong blades with 6-centimeter leaflets that are lanceolate to ovate, with crenate edges and a distinctive terminal three-lobed structure. The tiny fruits are ovate-oblong, measuring 1.5 to 2 millimeters in diameter.
Identification and appearance
Key characters: 1 sympatric species; key differences are stem rooting at nodes and narrower leaflet shape
Habitat and range
Habitat: Wet places
Elevation: generally < 1000 m
Outside California: native to Eurasia
Bloom period
Apium nodiflorum blooms May-Aug.
How to tell it apart
vs Oenanthe: Apium fruits are smooth without a crown; Oenanthe fruits are corky with a persistent crown.; vs Petroselinum: Apium grows in wet, marshy places; Petroselinum prefers drier disturbed areas and roadsides.; vs Conium: Conium has purple-spotted stems and musty odor; Apium has green unspotted stems.; vs Torilis: Torilis fruits are covered with hooked bristles; Apium fruits are smooth or ribbed.; vs Nasturtium: Nasturtium is in the mustard family with 4-petaled flowers; Apium has 5-petaled carrot-family flowers.
Frequently asked questions
Is Apium nodiflorum native to California?
No. Apium nodiflorum is not native to California (recorded as not native).
When does Apium nodiflorum bloom?
Apium nodiflorum blooms May-Aug.
What plant family does Apium nodiflorum belong to?
Apium nodiflorum is in the Apiaceae family, genus Apium.
What habitat does Apium nodiflorum grow in?
Apium nodiflorum grows in Wet places.
Related species
Other California species in the same genus, family, or bioregion.
Sources: Jepson eFlora · CalPhotos
Last updated 2026-10-07
Data from The California Species Project — 14,000+ California species with verified data from CNPS, CDFW, USFWS, Cal-IPC, and more.