The dynamics of Themeda triandra tillers in relation to burning in the Natal Drakensberg.

Abstract

Marked tillers of Themeda triandra were sampled regularly over a two year period in Highland Sourveld burnt annually in winter biennially in spring and after a single summer and early winter burning treatment. Parameters recorded were height of shoot apex, tiller mass, number of new lateral tillers and time of flowering. Monitoring of marked tillers before and after each burn enabled the life history of populations of tillers to be followed. There were no significant differences in survivorship between tillers in the annual winter and biennial spring burn treatments but winter burning stimulated the development of a greater number of daughters per parent. Both populations exhibited a constant death rate over the two year period. Only 8% of the marked T. triandra tillers survived the single summer burning treatment.

Keywords: demography; highland sourveld; life history; natal drakensberg; shoot apex; south africa; survivorship; themeda; themeda triandra; tiller; tiller dynamics; tiller mass; tillers

Journal of the Grassland Society of Southern Africa.