Floating-Attached Aquatic Weed Identification

Floating-Attached Aquatic Weeds: weeds with stems, leaves or flowers that may or may not protrude above the water's surface. These water weeds have roots attached to the substrate, lakebed or floor of the water body. Below is a list of Australian aquatic plants species that are considered weeds, links to products we supply and methods we recommend to use to help eradicate water weeds.

There are also 3 other types of Aquatic Weeds:

Aligator Weed

Species: Alternanthera philoxeroides    Family: Amaranthaceae

Distribution
NSW, QLD, TAS, VIC

Description
Ball shaped pinkish papery flower, leaves 2-7cm long. Forms dense floating or rooted mats. Is known to also grow on land. If you suspect you have Alligator Weed it is important to treat it as soon as possible as it is considered one of the worst weeds in Australia. It spreads vegetatively therefore no traces of the plant can be left behind otherwise it will continue to grow.

Mechanical Control

Cape Pond Lily

 Species: Aponogeton distachyos   Family: Aponogetonaceae

Distribution
NSW, SA, VIC

Description
Leaves up to 15cm long, leaf stems up to 20cm long, with white forked fragrant flower. Winter growing/winter flowering.

Life Cycle
Perennial

Origin
Introduced

Mechanical Control

Cape Waterlily

Species: Nymphaea caerulea [synonym Nymphaea capensis]    
Family: Nymphaeaceae

Distribution
QLD, NSW

Description
Also known as Blue Lotus. Leaves 30-40cm in diameter with wavy margins, bright purple/blue flowers up to 15cm in diameter. Often mistaken for the native lily Nymphaea gigantean which poses no threats. Care should be taken when identifying to ensure the native lily is not interfered with.

Life Cycle
Perennial

Origin
Introduced

Mechanical Control

Common Nardoo

Species: Marsilea drummondii    Family: Marsileaceae

Distribution
NSW, QLD, VIC, SA, NT, ACT, WA

Description
Can be confused with leaves of some species of clover. Fronds clover-like with 4-leaflets up to 3cm in diameter. Native Australian aquatic plant that is not normally problematic, however can pose an issue in nutrient-rich environments.

Life Cycle
Perennial

Origin
Native

Mechanical Control

Floating Pondweed

Species: Potamogeton sulcatus   Family: Potamogetonaceae

Distribution
SA, TAS, VIC

Description
Has submerged translucent leaves up to 20cm long and floating thick, waxy leaves up to 10cm long. Fruit has an emergent spike. Can cover the surface of channels, lakes and dams.

Life Cycle
Perennial

Origin
Native

Mechanical Control

Nardoo

Species: Marsilea mutica    Family: Marsileaceae

Distribution
NSW, NT, QLD, SA, VIC, WA

Description
Native fern common in drier areas, clover-like fronds with 4 leaflets up to 10cm in diameter. Glossy green with a characteristic brown or yellowish marking near the center. Native Australian aquatic plant that is not normally problematic, however can pose an issue in nutrient-rich environments.

Life Cycle
Perennial

Origin
Native

Mechanical Control

Native Waterlily

 Species: Nymphaea violacea    Family: Nymphaeaceae

Distribution
NT, QLD, WA

Description
Large leaves and flowers. Flowers can be blue, white or rarely pink. Mature leaves 50cm diameter, flowers 6-20cm across.

Life Cycle
Perennial

Origin
Native

Mechanical Control

Potamogeton Octandrus

Species: Potamogeton octandrus    Family: Potamogetonaceae

Distribution
NT, NSW, QLD, WA

Description
Flower cylindrical spiked fruit branches up to 1cm long. Narrow, elliptical floating bright green leaves up to 4cm long x 1cm wide.

Life Cycle
Perennial

Origin
Native

Mechanical Control

Swamp Lily

Species: Ottelia ovlifolia    Family: Hydrochariaceae

Distribution
NSW, QLD, VIC, SA, NT, ACT, WA

Description
Native with white flowers showing just above the water's surface. Showy flower 5cm diameter with 3 petals with maroon center, leaves up to 16cm long. long.

Life Cycle
Perennial/Annual

Origin
Native

Mechanical Control

Water Chestnut

Species: Trapa natans    Family:Trapaceae

Distribution
None at present

Description
Leaves rhombic with toothed margins, fruits large and spiny, flowers are white and tubular. Not yet recorded in Australia; if encountered, notify authorities.

Life Cycle
Annual

Origin
Introduced

Mechanical Control

Water Lettuce

Species: Pistia stratiotes    Family: Araceae

Distribution
TAS, ACT, NSW, QLD, NT, WA,

Description
Also known as water cabbage. It can completely cover water bodies, reducing oxygen, killing fish & attracting mosquito's. Can be 10cm tall and 30 cm wide. Reproduces rapidly by offshoots. Occurs in slow moving waterways in tropical and subtropical warmer temperate regions.

Life Cycle
Perennial

Origin
Native

Mechanical Control

        •  

Water Primrose

Species: Ludwigia peploides ssp. montevidensis    Family: Onagraceae

Distribution
NSW, QLD, SA, VIC

Description
Creeping and floating stems, alternate leaves up to 6cm long and 3cm wide. Stems up to 4m long. Yellow primrose-like flowers in summer.

Life Cycle
Perennial

Origin
Native

Mechanical Control

Water Snowflake

 Species: Nyphoides indica    Family: Menyanthaceae

Distribution
NSW, NT, QLD, WA

Description
Leaves up to 50cm diameter, flower usually snowy white with orange/yellow at base, hairy on inside surface.

Life Cycle
Perennial

Origin
Native

Mechanical Control

Yellow Waterlily

Species: Nymphaea mexicana    Family: Nymphaeaceae

Distribution
NSW, QLD

Description
Bright yellow flowers, with floating leaves. Each flower lasts one week. Once established, it becomes difficult to eradicate.

Life Cycle
Perennial

Origin
Introduced

Mechanical Control

Eurasian Water Milfoil

 Species: Myriophyllum spicatum    Family: Haloragaceae

Distribution
None at present

Description
Rhizomes rooted to 10m depth, surface reaching from 3-5m. Dissected 'feathery' leaves are in whorls of four, leaves contain 12 to 21 leaflets. Long stems that form surface reaching mats.

Life Cycle
Perennial

Origin
Introduced

Mechanical Control

Fanwort

Species: Cabomba caroliniana    Family: Cabombaceae

Distribution
NSW, QLD

Description
Submerged leaves are fan shaped, fine branches, giving a feathery look. Solitary flower 2cm diameter from white to pale yellow in colour with possible pinkish/purplish tinge.

Life Cycle
Perennial

Origin
Introduced

Mechanical Control

Parrots Feather/Thread of Life

Species: Myriophyllum aquaticum   Family: Haloragaceae

Distribution
NSW, QLD, TAS, VIC

Description
Leaves whorled, toothed, bright green or bluish-green, carried on stems to 50cm tall. Only female flowers in Australia: 4 triangular white sepals 0.5mm long with no petals.

Life Cycle
Perennial

Origin
Introduced

Mechanical Control

          •  

Red Watermilfoil

Species: Myriophyllum verrucosum    Family: Haloragaceae

Distribution
NSW, NT, QLD, SA, VIC, WA

Description
Red leaved stranded plants that flower with 4 petals and 4 sepals. Has emergent leaves of reddish-purplish hue.myriophy

Life Cycle
Perennial

Origin
Native

Mechanical Control

        •  

Watermilfoil

Species: Myriophyllum salsugineum   Family: Haloragaceae

Distribution
NSW, SA, TAS, VIC, WA

Description
Stems to c.4m long, 1.5-5mm diameter, Submerged leaves whorled; emergent leaves in whorls of 4 or 5, ovate, usually 5–8 mm long, 3–4 mm wide, entire or with a few short teeth towards apex, green to purplish.

Life Cycle
Perennial

Origin
Native

Mechanical Control

          •  

Yellow Bladderwort

Species: Utricularia gibba ssp. exoleta   Family: Lentibulariaceae

Distribution
NSW, QLD, NT, WA

Description
Mostly floating submerged except for emergent flowers of yellow with brown markings 6mm across. Stems reach 50cm with traps on leaves (1–2.5mm) that are used to trap insects.

Life Cycle
Perennial

Origin
Native

Mechanical Control

        •  
Scroll to Top