Hardwood Coppice Control Within Thinned Stands

Management of hardwood stands for sawlog production requires removing trees to allow room for those remaining to grow to a suitable size for sawlog. Eucalypts have a tendency to coppice (re-shoot) after felling. This can be problematic when thinning, because the objective of reducing competition can be made redundant by the coppicing of the thinned stumps. For thinning to be effective in eucalypts coppice must be controlled.

 

The two best options for controlling eucalyptus coppice are applying herbicide to cut stumps or to coppice foliage. Applying herbicide to freshly cut stumps can produce effective control when applied within 48 hours after thinning. A drawback of this method is the potential of ‘flashback’ whereby neighbouring crop trees die as a result of the herbicide being translocated through shared root systems. The second option is to apply herbicide to the foliage of the coppice once all shoots have appeared.

 

A number of trials have been conducted to determine the appropriate rate of herbicide to apply to coppice foliage of different eucalypts. The trials monitor the success of each application and the effect on neighbouring crop trees over time. For coppice control of Tasmanian blue gum see Forestry Fact Sheet 6: Second Rotation Tasmanian Blue Gum Plantations.

 

To date glyphosate has been found to be the most cost effective and efficient herbicide to control coppice and PIRSA Forestry has not experienced flashback when spraying coppice foliage with glyphosate. When the trials are complete a list of species and suitable application rates and methods will be made available.

 

For further information please contact PIRSA Forestry