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Eucalyptus melanophloia and E. populnea dominate large areas of savanna in eastern Australia. Under aboriginal management, fires probably occurred under a broad range of conditions, but under pastoral management, burning is avoided when soil moisture is low. This experiment subjected E. melanophloia and E. populnea seedlings to burning and moisture stress, to examine whether this change in burning regime could affect seedling survivorship. The findings suggest survivorship rates are 87-93% for unstressed seedlings with relatively large lignotubers (>12mm² plan area) and 56-66% for unstressed seedlings with small lignotubers. There was no substantial interactive effect between moisture stress and burning for E. melanophloia, but such an interaction was apparent for E. populnea, such that moisture stress multiplied the effect of burning. The timing of burning in relation to soil-moisture conditions may have an enduring effect on woodland structure where E. populnea is dominant. E. melanophloia seedlings are more resistant to burning, especially with moisture stress, and fire may not be limiting structural development in woodlands where this species dominates. However, a more detailed understanding of species demography is required, including the conditions required for germination, causes of seedling mortality and the time taken for seedlings to develop fire resistance in the field.
