Drying and burning properties of the wood of some Australian tree species.

Abstract

Material 2.5-yr-old was sampled for drying and burning studies from 15 species (12 Acacia species, Angophora costata, Casuarina cunninghamiana and Melaleuca leucadendra [M. leucadendron]) established in trial plots in SE Queensland. For the drying studies, 0.6-m lengths were dried under cover and weighed periodically until their weight approached stability. Each of the species was then tested as a fuel in the burning studies, using standardized simulated cooking fires. Drying models were derived in which initial moisture content, basic density, piece diameter and a developed drying factor were included as variables. The drying factor was found to have the greatest influence on drying rate. Data are presented on the initial moisture content, green density, basic density and computed drying times to 24% moisture content for each species. In each burning study, 800 g of air-dried fuel was burnt in a 20-litre fire bucket to heat 4 litre of water. The rate of fuel consumption, rate of temperature rise of the water and the heat energy used by the water were obtained for each species. The burning trials revealed that all the species tested should be acceptable as fuelwood. It was concluded that the emphasis in future studies should be on the drying behaviour of species rather than on the development of detailed quantitative information on burning properties. These properties are more appropriately described in terms of qualitative attributes such as the capacity of the wood to burn evenly, without smoke, crackling or sparking.