Extractives Yields and Polyflavanoid Contents ofAcacia mearnsiiBarks in Australia

Summary Bark samples of 94 individual Acacia mearnsii trees were collected from 20 provenances across the species' natural distribution in the Australian states of New South Wales, Victoria, South Australia and Tksmania and the yields, Stiasny values and the poly-flavanoid contents of the hot-water extractives were determined. The average extractives yield of all bark samples was 55.3%. The highest yields based on the provenance and on the individual tree were 64.6% and 71.1% respectively both were from Tasmania. The average Stiasny value of extractives from the 94 bark samples was 85.8% and all 20 provenances means were higher than 80.0%. Furthermore, the extractives from Victoria showed higher Stiansy values than those from other states. The average poly-flavanoid content of the 94 bark samples was 46.4%, while the highest provenance mean and individual tree value were 62.5% and 65.5%, which were from Victoria and Tksmania, respectively. The provenances in Victoria appear to provide the least variable quality of barks, with the highest polyflavanoid contents.