Weed Identification

Australia > NSW > > Sagittaria

Sagittaria

Sagittaria platyphylla

THIS PLANT HAS BEEN DECLARED A WEED OF NATIONAL SIGNIFICANCE

Alternative Name(s): Sagittaria graminea subsp. platyphylla.

Family: Alismataceae.

Form: Water plant

Origin: Native from USA to Panama.

Flowers/Seedhead: Inflorescence on a leafless stalk, always below leaf height, with 212 whorls of fls. Flowers with 3 white petals and 3 sepals, male flowers c. 3 cm wide and with reflexed sepals. Flowers mainly spring to autumn, depending on latitude.

Description: Perennial aquatic to about 1.2 m high with tubers commonly formed. Submerged leaves translucent, strap-like, to 50 cm long. Emergent leaves lanceolate to linear-lanceolate, blade to 28 cm long and to 10 cm wide on a long stalk. Fruit a cluster (head) 0.51.5 cm across, consisting of 1-seeded segments, each segment flattened, winged, 1.53 mm long.

Dispersal: Spread by seed, rhizomes, tubers and floating entire plants. Cultivated as an ornamental and this has aided spread.


White 3-petalled flower

Notes: Now widespread and common in N Victoria, SW NSW and around Sydney, Newcastle and SE Qld. Becoming increasingly common in irrigation supply channels, drains, shallow creeks and wetlands. Shade tolerant. Forms dense patches, obstructing water flow and producing luxuriant growth in enriched conditions. Competes vigorously with native waterplants.

References:

    Noxious Weeds of Australia.W. Parsons and E. Cuthbertson, 1992, pages 3436. Waterplants in Australia. G. Sainty and S. Jacobs, 4th edition, 2003, pages 262263.

Web References: Search Australian web sites for further information on this weed.


Seeds

Submerged strap leaves

Infestation in Wunghnu, Victoria

Tubers

This weed has been included in the WEEDeck field guide as card W13

More information about WEEDeck is available from Sainty & Associates Pty. Ltd.

 

Australia > NSW > > Sagittaria

BACK

National Weeds Strategy
Telephone: (03) 6344 9657
Fax: (03) 6343 1877
Email: jthorp@weeds.org.au

Privacy Statement

Legal Notice

Site Design - Computer Support Tasmania
Australian Weeds Committee