Sium suave (Water Parsnip)


Britton, N.L., and A. Brown. 1913. An illustrated flora of the northern United States, Canada and the British Possessions. 3 vols. Charles Scribner’s Sons, New York. Vol. 2: 656. Provided by Kentucky Native Plant Society. Scanned by Omnitek Inc.

Where Commonly Found:  Swamps, wet meadows, wet woodlands, steam margins, ditches and muddy shore throughout North America, CT, MA, ME, NH, NY, RI, VT.
How to Identify:
(For unfamiliar words: Wikipedia Glossary of Botanical Terms).
Go Botany Key for Sium suave.
Missouri Botanical Garden’s description of Sium suave. Click on more images.

Flower Color:  White
Flower Type:  Umbels
, flattish, each flower is 1/4″ wide, clusteed into a 1-1/2″ – 4-1/2″ umbel.
Flower Time:  July to September
Leaf Arrangement:  on stout, hollow, central smooth stem, ridged.
Leaf Type:  Compound, pinnately, divided into 5 – 17 pointed lanceolate leaflets, each 1/2″ – 6″ long. deep green leaves, with sharply toothed margins, total compound leaf is 4″ – 10″ long.  Submerged leaves are finely dissected.
Height:  2′ – 6′
Seed Collection:  Oval fruit, ribbed

Attracts:  Beneficial insects.
Use:  Naturalizing.
Light:  Full Sun to Part Shde
Hardiness Zone:  3 to 9 USDA Zone Map
Soils:  Medium to Wet
Notes:  Sium suave (Water Parsnip) is a water loving wildflower that could be useful in a rain garden, where moist soil is consistent.  Looks very similar to the very poisonous Water Hemlock so be very careful!
Native to all of the continental US, RARE in much of the South:  Biota of North America Program (BONAP) – North American Plant Atlas (NAPA).

Requested by Edgewood Nursery.

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