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The relative impacts of clearfelling followed by slash-burning, clearfelling, and no treatment were monitored for 2 years in two major types of eucalypt forest in south-eastern Tasmania. Rates of change in species cover were significantly greater in the burned area than in both the clearfell and control areas. More than half the species for which suitable data were available increased most in the burned area and least in the control. More higher plant taxa were present in the permanent burned plots 4 months after the burn than before the burn. By the last 8 months of recording, new taxa were invading at a rate of only 0.1 per month. Composites and shrubs constituted most of the late invaders. The behaviour of diversity measures was largely a function of the behaviour of a few of the taxa. Fire intensity, as measured by degree of soil baking, had a pronounced influence on species composition and cover. The species composition of aerially sown seed had little influence on the species composition of the eucalypt regeneration, with species not sown by the Forestry Commission recovering vegetatively, and much of the sown seed not resulting in seedling establishment. The clearfelling and burning, and clearfelling treatments did not result in the loss of any native species but there was substantial invasion by introduced herbs. However, lack of substantial impact in the short term does not guarantee the same in the long term.

An area of dry eucalypt forest on dolerite in southeastern Tasmania with comparable sites that were a) unlogged, b) clearfelled, c) clearfelled and slash-burned, was monitored over a 24 month period. Detailed records were made of plant species composition and cover on floristically similar fenced and unfenced permanent plots in two major vegetation types. Mammal faecal pellets were cleared from each of the unfenced plots and subsequently counted and attributed to species of origin. For the six combinations of treatment and vegetation type pellet deposition rate was highly correlated with differences in the rate of change of species cover between fenced and unfenced plots and the lifeform composition of the vegetation. The greatest changes were observed in the clearfelled, burned area, while there was relatively little change in the undisturbed forest. Grass and herb species were generally disadvantaged by mammal exclusion while shrubs and graminoids generally grew faster in the fenced plots.

Observations were made across 11-40-year-old fire boundaries in Tasmanian alpine areas of varying macroenvironment and flora. Organic matter and total nitrogen in the surface soil were significantly less where the vegetation had been recently burned. There were no significant differences between recently burned and recently unburned plots in contents of phosphorus, potassium, calcium or sodium or in pH. The burned plots contained few or no gymnosperms or deciduous shrubs, the most frequent dominants of the unburned vegetation. Most other shrubs were markedly less important in the burned than in the unburned plots, although most species of bolster form were little affected by fire, and some composite shrubs were most abundant on the burned plots. Most herbaceous species had equal or greater cover on the burned plots than on the unburned plots. The burned vegetation of the eastern mountains appeared to regenerate more quickly than that of the more oligotrophic western mountains.

An area of dry eucalypt forest on dolerite in southeastern Tasmania with comparable sites that were a) unlogged, b) clearfelled, c) clearfelled and slash-burned, was monitored over a 24 month period. Detailed records were made of plant species composition and cover on floristically similar fenced and unfenced permanent plots in two major vegetation types. Mammal faecal pellets were cleared from each of the unfenced plots and subsequently counted and attributed to species of origin. For the six combinations of treatment and vegetation type pellet deposition rate was highly correlated with differences in the rate of change of species cover between fenced and unfenced plots and the lifeform composition of the vegetation. The greatest changes were observed in the clearfelled, burned area, while there was relatively little change in the undisturbed forest. Grass and herb species were generally disadvantaged by mammal exclusion while shrubs and graminoids generally grew faster in the fenced plots.

Energy content and rate of flame front movement in various plant species and fuel components from the forests of southeastern Tasmania exhibited a range in values, and responses. Eucalypt dry forest species and fuel components showed the highest energy content and the greatest tendency to propagate fire whereas species from wet sclerophyll and gully habitats and Casuarina dry forest communities propagated fire less readily. Species from dry habitats have, in general, low ash contents, high energy levels, high volatile oil contents and low moisture contents. Wet habitat species have high percentages of moisture and ash. General support is given to the hypothesis that natural selection has favoured flammable characteristics in fire-dependent plant communities.

The relative impacts of clearfelling followed by slash-burning, clearfelling, and no treatment were monitored for 2 years in two major types of eucalypt forest in south-eastern Tasmania. Rates of change in species cover were significantly greater in the burned area than in both the clearfell and control areas. More than half the species for which suitable data were available increased most in the burned area and least in the control. More higher plant taxa were present in the permanent burned plots 4 months after the burn than before the burn. By the last 8 months of recording, new taxa were invading at a rate of only 0.1 per month. Composites and shrubs constituted most of the late invaders. The behaviour of diversity measures was largely a function of the behaviour of a few of the taxa. Fire intensity, as measured by degree of soil baking, had a pronounced influence on species composition and cover. The species composition of aerially sown seed had little influence on the species composition of the eucalypt regeneration, with species not sown by the Forestry Commission recovering vegetatively, and much of the sown seed not resulting in seedling establishment. The clearfelling and burning, and clearfelling treatments did not result in the loss of any native species but there was substantial invasion by introduced herbs. However, lack of substantial impact in the short term does not guarantee the same in the long term.

Observations were made across 11-40-year-old fire boundaries in Tasmanian alpine areas of varying macroenvironment and flora. Organic matter and total nitrogen in the surface soil were significantly less where the vegetation had been recently burned. There were no significant differences between recently burned and recently unburned plots in contents of phosphorus, potassium, calcium or sodium or in pH. The burned plots contained few or no gymnosperms or deciduous shrubs, the most frequent dominants of the unburned vegetation. Most other shrubs were markedly less important in the burned than in the unburned plots, although most species of bolster form were little affected by fire, and some composite shrubs were most abundant on the burned plots. Most herbaceous species had equal or greater cover on the burned plots than on the unburned plots. The burned vegetation of the eastern mountains appeared to regenerate more quickly than that of the more oligotrophic western mountains.