Use of environmental water allocations to conserve floodplain and wetland plants is becoming an increasingly common management tool. In south-eastern Australia, Moira grass (Pseudoraphis spinescens (R.Br.) Vickery) historically covered extensive areas within Barmah Forest where it is deemed to be ecologically significant and of high conservation value. The areal extent of Moira grass significantly declined throughout the forest during the Millennium drought (1996 – 2010). Natural flooding (2010 – 2012) failed to elicit an expected increase in the extent of Moira grass suggesting that this species may not have a viable long-lived seed bank. We investigated the existence and viability of the seed bank of Moira grass by (i) germination trials, (ii) identification of seeds within the sediment and (iii) estimates of seed viability. No plants were identified as Moira grass during the germination trial, however seeds of Moira grass were identified as being present in the sediment but the majority (98%) were not viable. In comparison, 16% of seeds collected from mature seed heads were found to be viable. Results from this study demonstrates an absence of a persistent long-lived seed bank of Moira grass at Barmah Forest. This suggests that to maintain Moira grass successive flood regimes may be need to encourage seed germination and that there is a need to manage existing stem fragments and rootstock.