The responses of the understorey of forests and woodlands of the Southern Tablelands to grazing and burning

Abstract

Field responses to various burning and grazing treatments in three sites on the Southern Tablelands were measured. Grazing by native mammals was unrestricted and continuous. Burning occurred once from fires of low intensity. Records of mortality, height growth and in some cases, seed production showed biologically significant effects of the treatments imposed on small plots. Dillwynia retorta plants were susceptible to a single fire but the species persisted through seedling germination. Other species showed vegetative survival to various extents from the fire. The burning-grazing combination was particularly potent in affecting survival, regeneration and growth of all species. Supplementary evidence of species' responses were gathered from the treatment of selected individuals in the field and laboratory.Some of the implications of these results and in particular the practice of controlled burning are discussed in relation to the management of reserves set aside for flora and fauna conservation.

Herbivory, serotiny and seedling defence in Western Australian Proteaceae

“…Significant amongst these is the elimination, or at least significant reduction, of herbivore populations. A number of studies have highlighted the interaction between herbivory and fire (Leigh and Holgate 1979;Whelan and Main 1979;Bond 1984;Mills 1986;Tyler 1995). However, while these experiments have identified the overall impact of herbivores on postfire and inter-fire seedling populations using herbivoreexclusion techniques, this kind of approach sheds little light on the actual mechanisms involved (Hulme 1996).…”

The impact of grazing pressure in clearfelled, burned and undisturbed eucalypt forest

“…However, the interactions between other environmental variables and grazing impact are not well understood, and little is known of the relationships between disturbance, grazing pressure and vegetation change. Leigh & Holgate (1979) found that the impact of mammal grazing on vegetation was greater in burned than in unburned plots, thereby suggesting the hypothesis that vegetation change directly attributable to herbivores is increased by increasing disturbance. A study of the impact of various silvicultural techniques on two * Nomenclature of plant species follows Curtis & Morris (1975).…”

“…The exclusion of grazing had the positive management effects of reducing the area of soil susceptible to erosion and increasing the beauty of floral displays (cf. Leigh & Holgate, 1979). However, marsupial grazing appears to be the better option from the point of view of nature conservation.…”

A critical review of the science underpinning fire management in the high altitude ecosystems of south-eastern Australia

“…These experiments include studies of resprouting in eucalypts (Noble, 1984), soil nutrients (Ellis and Graley, 1983), soil temperatures (Raison et al, 1986a), streamflow (O'Loughlin et al, 1983) and the combined effects of grazing and burning (Bryant, 1973;Leigh and Holgate, 1979). Chronosequence (space for time) studies frequently have to make assumptions that all sites (that are often geographically distant) had the same initial status (floristic, soil, water, nutrient and fuel) and have experienced similar conditions (e.g.…”