"As well as the rhizome, the young shoots which appear in the spring and the raw young flower-stalks were also eaten (Beveridge 1883, 36, and 1889, 20; Robinson 1840, 996), and the bases of the mature shoots and leaves always remain soft and edible.
Two main methods of cooking are recorded--roasting in the ashes, or steaming in an earth oven. Mitchell, on the Lachlan River, described roasting as follows (1839, vol 2, 53, 60, 384):The natives gather the roots and carry them on their heads in great bundles
within a piece of net ... The root is taken in lengths of 8-10 in., they
peel off the outer rind, lay it a little before the fire, then twist and
loosen the fibres, when a quantity of gluten, exactly resembling wheaten
flour, may be shaken out. This gluten they call balyan.
Notice that the less-productive outer cortex was discarded before cooking. Although Mitchell described it first as cooked by being laid on the fire, later, starting down the Murrumbidgee from the Lachlan junction, he described `lofty mounds of burnt clay or ashes ... [in which] the balyan is prepared' (1839, 80-81). On the lower Murray River, the rhizomes were cooked on a heap of limestone which had been heated by fire, with another layer of heated stones and wet grass laid over the top, the whole then enclosed in a mound of sand (Angas 1847b, 85). Krefft (1865, 361), on the middle Murray, said it was harvested probably in late summer, and lived on for several months. It was cooked in a hole in the ground, and was carried about as provisions. Beveridge, at Tyntynder, on the Murray River below Swan Hill, remarked that more of it could have been used, but `it requires considerable labor to dig'; he indicated that it was cooked in an earth oven using balls of clay as heat retainers and gave a detailed description of how the oven was made. A hole, 3 feet in diameter and 18 inches deep, was dug by the women. Any pieces of clay about the size of cricket balls were placed to one side. The hole was swept out with grass or boughs, and filled with firewood, which was then set alight with the clay balls on top. When the fire had died down, the clay balls were removed with two sticks used as tongs, and the ashes were swept out. The hole was lined with moistened grass on which the rhizomes were placed, more moistened grass was used as a cover, and the baked clay nodules placed on top. The whole was then covered with earth until the food was cooked (Beveridge 1889, 19). Mounds still remaining on the flood-plain are full of these baked clay balls (Coutts et al 1979, 60, 69; Frankel 1991, 74-82) and were certainly cooking sites for Cumbungi and other foods. The action of earth ovens is to steam the food, and is an efficient way of cooking for a group. The technique was subject to minor variations (see Browne, in Finnis 1966, 42, for example). J Mathew, on the Murrumbidgee River, described very large earth ovens holding `half a ton' of rhizomes, prepared for large gatherings of people:
A hole of circular outline 3-4ft deep and 15-20ft across was made. The roots were placed in the centre on a pile of dry wood. On the surface were
strewn layers of long grass and light sticks. The fire was lit and the excavated earth returned as a covering. The time for cooking might be several days. When done, water was poured on the oven to cool it. (Mathew1899, 91)
After cooking, the practice was to strip off the cortex, chew the central part of the rhizome to remove the starch, and to spit out the fibres, which could then be retained for making string.
In the Brisbane area, the rhizomes appear to have been chewed raw; the fibre was discarded (Petrie 1904, 92). In southern Western Australia, the rhizomes were cleaned and pounded between flat stones into a paste, presumably to break up the fibre, and then made into a cake and baked (Grey 1841, vol 2, 291; Moore 1884, 81). Morris (1943, 169) said that the pollen was used for food in Victoria, but gave no reference. It is certainly produced copiously. In New Zealand, the Maori ate the pollen, made into cakes or gruel, and also the centres of the rhizomes and the young leaves (Crowe 1981, 107-08"http://findarticles.com/p/articles/mi_hb3326/is_1_1999/ai_n28742509/pg_7/
Cattail Pond in Wychwood Forest where I live.
This plant is also note worthy for its use as thatching & matting for shelter use inside & out.