Perennial grass survival in drought
Perennial grass survival in drought Conference Paper
16th Australian Rangeland Society Biennial Conference
- Author(s): Hodgkinson, K.C.
- Published: 2010
- Publisher: Australian Rangeland Society
Abstract: The survival of perennial grass plants in drought is of scientific and applied interest; scientists want to know why species differ in ability to cope with individual and combined stresses of drought, grazing and fire, and graziers want to maximise survival of desirable forage plants because natural replacement can be very unreliable. Five species taken from Canberra grasslands were glasshouse-grown in large 1 m tall pots for one year and then watering ceased. The rate of passage through early drought stages differed between species. Rewatering plants at various times from onset of full drought was used to determine viability from which survivorship curves were generated. Three native grasses (Themeda triandra, Austrodanthonia auriculata and Bothriochloa macra) and one exotic species (Phalaris aquatica) had similar survivorship curves with 50% survival between 60 and 120 days. For the second exotic species, Eragrostis curvula, 50% survival was at 260 days. Density of viable tillers generally declined during drought before plant death.