Sium latifolium (L) Greater Water Parsnip
NOMENCLATURE
Sium : from Greek, ________ : sion : water plant.
latifolium : broad leaved.
OTHER NAMES : Sium segetum. Broad leaved water parnsip, water hemlock.
BSBI Picture Link to Sium latifolium
BOTANICAL DESCRIPTION
TYPE : stout erect, perennial, poisonous. Hel.
HEIGHT : 40-200 cm. STEM : Hollow grooved.
UMBELS : compound, terminal, flat topped 6-10cm diam. 20-30 smooth rays 1.5-4 cm .
Peduncle < to > than rays, leaf opposed, smooth. Terminal hermaphrodite. Lateral male.
LEAVES : submerged: 2-3 pinnate, linear lobes, present only in spring. Aerial : simply
pinnate, with 3-6(16) pairs of lobes. 12 x 4 cm, sessile, lanceolate to ovate, unequal at
base, serrate, with cartilaginous margin and teeth. Lower lvs long petiolate, the upper
with short sheathing petioles. Cotyledons contracted into a petiole.
BRACTS : 2-6, sometimes large, leaf like. Bracteoles 3-6, lanceolate.
FLOWERS : white. Petals papillose beneath, styles form a stylopodium. Fl. 7-8.
FRUIT : 3-4mm, ovoid, laterally compressed, constricted at commisure. Mericarps : thick
prominent ridges. 3 superficial vittae. Carpophore present. Pedicels 5-10mm. Styles
v. short and stout, recurved in fruit. Stigma spathulate. 2n=20.
HABITAT : shallow water, fen ditches.
DISTRIBUTION : local, mainly S.E. of a line from Humber to Bristol Channel, decreasing.
C. Ire.: Shannon & Erne. Most of Europe, Siberia.
BSBI Distribution Map for Sium latifolium (UK)
POISONOUS ROOTS : No harm to pigs and ox. Adds disagreeable taste to milk.
EXTERNAL LINKS FOR Sium latifolium
These links to trusted websites and institutions may provide in depth or additional information regards cultivation, chemistry, edibility, images etc. for the species. Links last updated Aug 2012.
Wikipedia (EU) Plants For a Future (UK)
Bio Info (UK) Nature Gate (FIN)
Environment Agency (UK)
UK Wildflowers (UK) Habitats (N.I.)
Norflok Biodiversity Partnership (UK)