THE SUGAR AND NITROGEN-CONTENT OF THE GUMS OF ACACIA SPECIES IN THE MOUNTAIN ASH AND ALPINE ASH FORESTS OF CENTRAL VICTORIA AND ITS POTENTIAL IMPLICATIONS FOR EXUDIVOROUS ARBOREAL MARSUPIALS

Chemical analysis of the total sugar and total nitrogen content of Aca cia dealbata, Acacia obliquinervia and Acacia frigescens gum exudate w as completed. These trees were located within stands of 53 year old Mo untain Ash, Eucalyptus regnans and Alpine Ash, Eucalyptus delegatensis forest in the Central Highlands of Victoria, southeastern Australia. Values for sugar content ranged from 24 to 68% per sample. Gum samples that were collected in E. regnans forests had a significantly lower ( P < 0.05) sugar content than those from stands dominated by E. delegat ensis. Statistical analyses using Scheffe's S-test indicated that ther e was a significant difference in the sugar content of gums between A. dealbata and A. frigescens but not between A. dealbata and A. obliqui nervia or A. obliquinervia and A.frigescens. Values for the nitrogen c ontent of Acacia gum varied from 0.2 to 0.7% per sample. Statistical a nalyses revealed that nitrogen content was significantly influenced (P < 0.05) by a combination of three interacting factors: (i) Acacia spe cies; (ii) tree diameter; and (iii) forest type. Therefore, the findin gs of this study indicate that the sugar and nitrogen content of Acaci a gum may vary between forest types and tree species. The gum of Acaci a species is an important source of food for several species of arbore al marsupials, and differences in sugar and nitrogen content could be a factor potentially influencing the distribution and abundance of the se animals.