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Oenanthe sarmentosa

Pacific Water Parsley

At a Glance: Semi-aquatic, often reclining or scrambling herb, with stem tips ascending or curled and small flat-topped clusters of white flowers.

Height: Up to 40 inches (1 meter).
Growth Form: Herb.
Stems: Fibrous and succulent, but usually weak and soft, developing a dark red tinge late in the season.
Leaves: Celery-like odor and shape; 2-3 times coarsely pinnately divided, oblong to egg-shaped in outline; leaflets toothed and cleft with primary veins directed to teeth tips; size: leaflets 1-6 cm; color: green.
Flowers: Tiny flowers in 5-20 compact clusters on 1-3 cm long stalks subtended by 0-few, narrow, leafy bracts; primary color: white, sometimes pink tinged; size: small; shape: compound umbels.
Flowering Period: May, June, July.
Fruits: Mature late summer; ribs broader than narrow intervals; shape: barrel; size: 2.5-3.5 mm long by 2 mm wide; color: maroon.


Photo © 2003, Starflower Foundation

Sun/Shade Tolerance	Hydrology	Elevation Range
Shade or sun. full sun > 80% mostly sunny 60%-80% partial sun and shade 40%- 60% mostly shady 60%-80% full shade > 80%	wet moist dry Wetland Indicator Status: OBL (obligate wetland)	low elevation mid elevation sub-alpine high elevation

Soil Preferences
Saturated year-round. Occupies lowest or wettest areas of wetlands.
sandy soils gravelly soils clay soils muddy soils peaty soils	well drained soils shallow soils deep soils acidic soils basic soils	humic soils nutrient rich soils nutrient poor soils mineral soils organic soils

Habitat Preferences
Aquatic and Wetland: Ponds or lakes Shallow pools Sloughs Swales or wet ditches Seasonally inundated areas Marshes or swamps Aquatic bed wetlands Emergent wetlands Scrub-shrub wetlands Forested wetlands Bogs, fens Seeps, springs Shorelines and Riparian: Lake shores Bog margins Streams or rivers Stream or river banks Riparian corridors River bars Floodplains Bottomlands Alluvial areas	Saltwater Areas: In or near saltwater Mud flats Tidal areas Estuaries Saltmarshes Brackish water Seashores Coastal dunes or beaches Rocky or Gravelly Areas: Coastal bluffs Cliffs Rocky slopes Outcrops Crevices Glacial outwash Gullies Slide areas Sub-alpine and Alpine: Heaths Snow beds Tundra Avalanche tracks	Forests and Thickets: Forests and woods Open forests Coniferous forests Old growth forests Deciduous forests Mixed forests Nurse logs Forest edges, openings, or clearings Thickets Meadows and Fields: Pastures or fields Meadows or grassy areas Mossy areas Disturbed Areas: Roadsides Trailsides Logged sites Burned areas Disturbed sites

Wildlife Value
Berries Seeds Nectar for hummingbirds Nectar for butterflies Host for insect larvae Thickets and shelter Thorny or protective cover	Other Wildlife: Used as spawning vegetation by Red-legged frog and Northwestern salamander.

Ethnobotanical Uses and Other Facts

Medicinal Uses: Used as a laxative, stomach medicine, and a headache medicine.
Food Uses: Tubers were cooked and eaten.
Toxicity: Is reputed to be toxic, due to its resemblance to water-hemlock which is very poisonous..

Ecological Importance: Produces significant above-ground biomass, growing very densely, and therefore can be useful in slowing water flow to enable sediment settling. Tolerant of replanting, making it useful in wetland restoration in shallow aquatic settings.

Name Info: Some species of the genus were used in Greece to flavor wine so Oenanthe comes from the Greek "ionois" (wine) and "anthos" (flower). When the stems touch or lie on the ground they send out long runners from the nodes, which is described by sarmentosa.

Suggested References

Cooke, S.S. A Field Guide to the Common Wetland Plants of Western Washington and Northwetern Oregon. Seattle Audubon Society and Washington Native Plant Society. Page 151.
Guard, B.J. 1995. Wetland Plants of Oregon & Washington. Lone Pine Publishing. Page 66.
Hickman, J.C., ed. 1993. The Jepson Manual: Higher Plants of California. University of California Press. Page 167.
Hitchcock, C.L., A. Cronquist. 1973. Vascular Plants of the Pacific Northwest. University of Washington Press. Page 334.
Jacobson A.L. 2001. Wild Plants of Greater Seattle. Published by author. Page 244.
Link, R. 1999. Landscaping for Wildlife in the Pacific Northwest. University of Washington Press. Page 64.
Lyons, C., W. Merilees. Trees and Shrubs to Know in Washington and British Columbia. Lone Pine Publishing. Page 206.
Pojar, J., A. Mackinnon. 1994. Plants of the Pacific Northwest Coast. Lone Pine Publishing. Page 216.

The landscaping and restoration information provided on this page is taken from Starflower Foundation Image Herbarium. All photographs © Starflower Foundation unless otherwise noted.