Growth, seed production and effect of defoliation in an early flowering perennial grass, Alloteropsis semialata (Poaceae), on Cape York Peninsula, Australia

Alloteropsis semialata (R.Br.) A.Hitchc. is one of the first perennial gras ses in monsoonal Australia to produce seed at the start of the wet season. Patterns of growth and seed production and seed dynamics of Alloteropsis se mialata were examined in this study, along with the effects of partial defo liation. Growth of Alloteropsis semialata tussocks started with the first p re-wet-season rains, and was then interrupted during a period with little r ain. Growth ceased before the end of the wet season, indicating that factor s other than moisture availability were limiting. Seeds of Alloteropsis sem ialata were germinable on production, but did not remain viable or persist on the soil surface through the dry season. Most seeds and young seedlings were harvested and no seedlings were recruited. Inflorescence production in creased with plant size. Moderate defoliation in the early wet season had n o impact on plant growth, but reduced inflorescence and seed production for at least 2 years. Absence of a seed bank and early wet-season flowering me an that Alloteropsis semialata is likely to be sensitive to long-term over- grazing.