Food resources in roots of messmate stringybark and Victorian blue gum at Mount Cole, as affected by season and harvesting treatments, and implication for Armillaria control.  I. B. Tomkins, J. D. Kellas and R. O. Squire.  March 1986.  18pp. (unpubl.)

SUMMARY

Measurements of seasonal variations in starch and soluble sugar in sapwood were made for roots of standing trees and stumps of messmate stringybark and Victorian blue gum over a two year period in four mature stands at Mount Cole. Previously established seasonal variations were confirmed for messmate stringybark standing trees, and similar patterns established for Victorian blue gum in the first year of the study. Victorian blue gum had higher starch reserves, but similar sugar reserves to messmate stringybark.

At the commencement of the second year of the study, four harvesting treatments were applied to the stands. These were an uncut control, a selection treatment creating gaps approximately 15 m in diameter, a shelterwood treatment retaining 10 m²ha^-1 of basal area and a clearcut treatment.

There was no effect of cutting on the starch and sugar reserves of retained trees. However, reduction of starch levels in roots of stumps appears to act to maintain normal levels and seasonal variation of sugars for at least twelve months after cutting.

The results suggest that there is only limited scope for manipulating the food base for Armillaria by varying harvesting treatment and/or season of treatment.

Also published:

Tomkins, I.B., Kellas, J.D. and Squire, R.O. (1989)  Effects of season and harvesting treatments on soluble sugar and starch levels in Eucalyptus obliqua and E. globulus ssp. globulus in roots, and implications for Armillaria control.  Aust. J. Bot. 37: 305-12.

Kellas, J.D., Kile, G.A., Jarrett, R.G. and Morgan, B.J.T. (1987)  The occurrence and effects of Armillaria luteobubalina following partial cutting in mixed eucalypt stands in the Wombat Forest, Victoria.  Aust. For. Res. 17: 263-276.