A Seagrass Tile
One of the cheapest floor coverings around is seagrass tiles. I have always wondered where the seagrass came from and asked around to no avail. On a recent trip to Cape York Peninsula at the tip of Australia where I was doing an environmental survey (Cape Alumina project), I found a large sedge growing on the freshwater intertidal section of the Wenlock River. Formal identification revealed this sedge to be Actinoscirpus grossus. It took a lot of googling to connect this plant with the floor covering that it becomes.
Actinoscirpus grossus inflorescence
Greater Club-rush is the common name that seems to have the least potential for confusion. Actinoscirpus grossus has several common names, however these names are mostly in local languages as the sedge is found from Australia to Japan to India in both temperate and tropical climates.
This photo shows the inflorescence of the sedge which is held about 1 m above the water on a pithy triangular papyrus like stalk. In this habitat the tidal range is about 1 m and the sedge forms patches along the margins of the river. I very carefully collected a sample from here with a long stick which was just as well as I later saw a 4 m crocodile surface just beyond the sedges that would have been trying to collect me.
Actinoscirpus grossus in lower Wenlock River
Some web documents that I used to confirm my information are:
http://www.oswaldasia.org/species/a/actgr/actgr_en.html
http://202.90.141.226/publication/techno%20flyer/DYEING.pdf
http://www.agprime.com/Weeds/Invasive/FactSheets/Actinoscirpus%20grossus.pdf