Fine fuel in the dry sclerophyll forests of south-eastern New South Wales

Summary

Fine fuel samples, 4506 in total, were collected from 24 sites in the dry sclerophyll forests of south-eastern NSW in six of the years between 1972 and 1986. In multi-aged stands that had not been disturbed for at least 5 y, mean weight of fine fuel over all years was 10.4 t ha⁻¹, and between years it ranged from 8.9 to 14.41 ha⁻¹. In regrowth stands developing following wildfire, mean weight of fine fuel varied according to the stage of stand development: 6.7 t ha⁻¹ at 3 y old, 16.91 ha⁻¹ at 11 y old, 10.0 t ha⁻¹ at 22 y old. In these stands the maximum weight of fine fuel probably occurs at a stand age of about 10 y.

In both multi-aged and fire regrowth stands, annual litterfall was about 41 ha⁻¹, which was high relative to the weights of fine fuel. It is estimated that fuel would accumulate from zero to 95% of the ‘steady state’ weight in 8 y in multi-aged and older regrowth stands. Weight of residual fine fuel, and annual variation in litterfall and decomposition, influence the re-accumulation of fine fuels in the forest. Limited sampling in stands which had been logged and silviculturally treated provided an indication of the effects of some forest management activities. The greatest weight of fine fuel for any site was 20.6 t ha⁻¹, measured 4 y after non-commercial thinning in a fire regrowth stand. Integrated logging in multi-aged stands caused small increases in the weight of fine fuel, while post-logging burning had little effect.

Fire management benefits associated with lesser weights of fine fuel could be achieved by prescribed burning at a landscape scale at intervals of 5–8 y.

Keywords:

• forest litter
• litter weight
• dry matter accumulation
• fuel appraisals
• forest fires
• forestry practices
• sclerophyllous forests