Estuarine Pondweed, Tassel Pondweed or Ditch Grass
The Pondweed is prolific at the heads of estuaries. It is submerged and forms dense mats that are cursed by boatmen because of the damage they cause to propellers.
Stems and leaves are thin, grass-like and tangled. Flower stalk short and straight. Size: 1 m long, 1 mm wide.
Ruppia cirrhosa: flower stalk coiled. Potamogeton pectinatus: flowers clustered on a spike.
The Pondweed is not a marine plant despite its species name, but it is rather a freshwater plant that tolerates saltwater. The plant usually self pollinates but it can be pollinated by pollen that floats on the water after being released by the flower.
The fruits of the Pondweed are dispersed by fish and waterfowl that feed on them but the plant can also sprout from its rhizomes and form colonies.