Plants of South Eastern New South Wales

Potamogeton cheesemanii

Flowering stem. Photographer Richard Hartland, Beaufort

Flowering plants. Photographer Richard Hartland, Beaufort

Common name

Pondweed

Family

Potamogetonaceae

Where found

Aquatic in permanent waterbodies and streams. Widespread.

Notes

Aquatic perennial herb, rhizomatous. Stems round to flattened in cross section, to about 2 m long. Leaves alternating along the stems, with a sheath at the base, hairless. Submerged leaves thin and translucent, 5–10 cm long, 5–25 mm wide, stalkless or with short stalks, translucent, with 5–12 main longitudinal veins, margins entire to slightly wavy, bases and tips tapered. Floating leaves 1.5–5 cm long, 15–35 mm wide, stalked, forming a terminal rosette; more or less thick and leathery, dull, with 10–20 main longitudinal veins; bases rounded to cordate, tips blunt or pointed. Upper submerged leaves more like the floating leaves, but with  much longer stalks than the floating leaves. Flowering stems above the water. Flowers 3–4 mm in diameter, with 4 'petals'. Flowering spikes about 12–24 flowered, 10–25 mm long at the seeding stage (excluding the non-seeding part of the axis), located on rosettes of floating leaves. Fruit reddish, brownish or green, the seeding spike slightly curved down. Flowers and fruits Sep.–Apr. 

All native plants on unleased land in the ACT are protected.

PlantNET description:  http://plantnet.rbgsyd.nsw.gov.au/cgi-bin/NSWfl.pl?page=nswfl&lvl=sp&name=Potamogeton~cheesemanii  (accessed 2 February, 2021)