The CRC for Forestry in Australia has produced a bulletin examining volume losses when using different feller buncher heads.Bulletin 22 of March 2012 was compiled by Martin Strandgard (University of Melbourne) and Rick Mitchell (CRC for Forestry). The bulletin compared shear, hotsaw (continuous disc saw) and chainsaw felling heads operating in Eucalyptus nitens and globulus pulpwood plantations. The research compared the heads in terms of estimated volume and value lost in stumps and saw kerf during harvesting. Other aspects such as productivity, site impacts and fire risk were also considered.
The results showed that using shear heads can recover more volume and value per hectare than the other feller buncher heads due to lower stump heights and a lack of saw kerf. Chainsaw heads were better suited to larger trees and stands producing sawlogs. The value lost (in Australian dollars) per hectare due to stumps and saw kerf, assuming a yield of 230 m3 per ha and stumpage of $ 30 per m3, was $ 251 for the chainsaw, $ 203 for the hotsaw and $ 16 for the shear.
The bulletin also discusses the disadvantages and advantages of using the three types of feller buncher heads. Please contact Mark Brown at mbrown2@usc.edu.au for a copy of the bulletin, or visit www.crcforestry.com.au for more research activities carried out by the CRC for Forestry.