Softwood-plantation-residues

A total harvestable residue figure of 30-155t/ha over a 25 year harvest rotation was sourced from the literature for P.radiata. The primary source was the RIRDC report 11/177 by F.Ximenes et al 2012 and was confirmed by industry consultation for P.radiata residues. An average figure of 95t/ha/25yrs is used and these figures were then multiplied by the area of plantation to give an indication of average annual harvest residues potentially available for each LGA.

The core 2016 ABARE Australian plantation statistics shows the spatial extent of the softwood plantation. This and the related metadata statement can be found at,

http://www.agriculture.gov.au/abares/research-topics/forests#australian-plantation--statistics

Limitations The residue estimates provide a range of possible production tonnages. The actual figures will vary in the field and will ultimately require more in depth investigation for any possible project application. In addition, the plantation statistics are based on 2016 data and plantation areas may have changed in the intervening period.

It is also important to note that the calculations show total plantation area and the possible residues present. A harvest interval of 25yrs was assumed and total residues over a 25yr period were divided by 25 to give an estimate of residues that may be available on yearly basis. How much of that estate is harvested in a given year and therefor what proportion of these residues is practically available will depend on block age, growth rate and harvest schedules.

Dry weight tonnes per year has been calculated using a moisture content of 32% and assumes that 4% of the total area will be harvested every year. In reality this will vary between harvest zones and is intended to give an indication of yearly dry tonnes available.