Plants

Grey Mangrove

A medium-sized tree or occasionally a shrub with a well-defined trunk and numerous vertical peg (aerial) roots (pneumatophores). Leaves are green above and greyish below. Seeds germinate on the tree and fall off normally in summer. Only a few grey mangroves exist in the lake, located to the south-west of Windang Bridge. More have been transplanted in the inter-tidal zone of the lake to increase wildlife habitat and to protect the shoreline from erosion.

Swamp She-oak

This typical inhabitant of the saltmarsh wetlands of the lake grows up to 20 m tall. The tree has erect branches and grey, cracked, flaky bark. Round cones (fruit) up to 12 mm in diameter are produced. Casuarinas flower in spring-summer. Around Lake Illawarra the species grows in the upper saltmarsh zone all around the lake, especially along Mullet Creek and Macquarie Rivulet.

Waterbuttons

A perennial, succulent plant up to 17 cm tall. Flowers are yellow and flowering occurs throughout most of the year. Around Lake Illawarra the species occurs mainly in the upper saltmarsh zone and may extend into the middle saltmarsh zone where there is a continuous seepage of freshwater.

Spreading Flax-lily

A perennial herb up to 80 cm tall. Flowers are violet-pink in colour and flowering occurs in summer. Produces round, azure-blue fruit up to 8 mm in diameter. Around Lake Illawarra the species grows in the upper saltmarsh zone and is mostly associated with sedges and grasses.

Sea Rush

A perennial, erect, spiny rush up to 130 cm tall with cylindrical stems. Flowers are reddish-brown in colour and flowering occurs in spring-early summer. Around Lake Illawarra the species is found occasionally as isolated patches in the middle saltmarsh zone, but usually occupies the upper saltmarsh zone. Juncus is often associated with the common reed (Phragmites australis), usually occupying the back fringe of the Phragmites belt.

Swamp Lily

A perennial, large erect and bulbous plant up to 2 m tall. Thick leaves up to 80 cm long and 25 cm wide. A native species which flowers in late spring-summer. Around Lake Illawarra the species is found in the upper saltmarsh zone along Windang Peninsula and the south-eastern corner of Griffins Bay.

Swamp Weed

A perennial herb with creeping stems and thick leaves 2 to 8 cm long usually shining. Flowers a white fan-shape, flowering in summer. Around Lake Illawarra it grows in the middle and upper saltmarsh on sandy soil.

Eelgrass

Seagrasses are flowering plants adapted for life submerged in a marine or estuarine environment. Like flowering plants on land they produce flowers and seeds.

Eelgrass is the most abundant seagrass in Lake Illawarra and often seen as a dark olive or reddish green mass of leaves in the shallow water of Lake Illawarra. It is a perennial estuarine water plant with leaves 7-50 cm long and 2-5 mm wide. Erect flowering stems are produced after several years, which break off at the base releasing seed as it floats. Valuable for stabilising sediments, this species also provides habitats suitable for invertebrates and fish.