This for some reason is hard for me..i can get a bit generic with the term 'rush' and there are many different types that hold onto their flowers for ages and i get confused coz the flowers are all brown..
1) Tufting - a tufted rush is a Juncus Usitatus, also if its a mature plant under 1 m it is also a Juncus.
2) Flower - the flower of the Juncus is actually white and beautiful but goes brown quickly.. if u found a nice white flower on a reed its a Juncus.. There is a Juncus Acutus (which is a weed and it will spike you) and a Juncus Kraussi which you will find in more salty waters
3) The Juncus is the common one, so remember to go from there, but they all share the same habitat around waterways in Australia.
4) Leaf/Blades/Stems - the Bulboschoenus is the only one with leaf blades common around the flower, sometimes you will find one on a Schoeneplectus. The diameter of stems of Bulb. and Schoen are from half a cm but the Juncus stem diameter only gets as large as .3 of a cm.
5) the Bubloschenus flowers are in clusters but the actual flower of the Schoeneplectus is an umbel (both create the visual of width) both have branches 8-10cm long.
6) all these rushes have edible roots the bulboschoenus is definitely the most edible for its white roots taste like coconut milk and is medicinal as an anti-contraceptive.