Area of jarrah forest logged under
various silvicultural prescriptions 1986-2020

Prepared by Beth Schultz for the South-West Forests Defence Foundation Inc. – January 2021

Under current FMP 2014-2023 except 2016-2017            5,219 = 1,043 pa       30,586* = 5,097 pa
Source:  CALM Annual Reports 1986-1987 – 2005-2006, DEC Annual Reports 2006-2007 – 2008-2009; Yearbook 2009-2010 – 2012-2013;
Department of Parks and Wildlife Yearbook 2013-2014 – 2015-2016; Legislative Council Question on Notice No. 335 of 2020
*Does not include areas cleared for mining or utilities.

Department of Conservation and Land Management 2004, Silvicultural Practice in the Jarrah Forest, Sustainable Forest Management Series, SFM Guideline No. 1.

Gap creation (release regeneration – virtual clearfelling) – jarrah regeneration encouraged to develop unimpeded into saplings, poles and mature trees by the removal of competing overstorey

Regeneration release by gap creation will be sought where there are insufficient crop trees to merit thinning (i.e. less than 50% of required stocking), but where the stocking of ground coppice and saplings will adequately regenerate the gaps created by logging.

Each gap is to be no more than 10 hectares in area and separated from the next gap by Temporary Exclusion Areas (TEAS) 50 to 100 metres wide.  It was recommended that TEAS be retained until the recently logged forest had recovered to a state where is provided good quality habitat for native fauna and it was intended that they be left uncut for 15 to 20 years but some have been logged sooner.

Shelterwood (establish regeneration) – seedlings encouraged to establish and develop into ground coppice by reducing the competition of the overstorey. A forest canopy is maintained to provide a continuity of forest values until the ground coppice is developed and capable of response to release.

A shelterwood is created where there is an inadequate stocking of crop trees for thinning and where there is insufficient ground coppice and saplings available for immediate release. The shelterwood overstorey is retained to provide seed for regeneration and a continuity of forest values until ground coppice has developed to the stage where it is capable of rapid growth following release.

There is no limit to the area that can be logged in a single shelterwood.

Thinning – promote growth on retained trees

The desirable retained density of crop trees varies with their size. When crop trees are small, the aim is to grow individual trees rapidly to sawlog sizes. Once crop trees are of sawlog size, the aim is to maximise the growth of sawlog volume per hectare. To achieve that, a relatively higher basal area is retained as the average tree size increases.

There is no limit to the area that can be thinned.

Selective cut in dieback – retain and promote resistant species and individuals on Phytophthora cinnamomi infested forest.

This silvicultural method aims to:

• Promote an ecosystem of resistant species on sites infested with Phytophthora cinnamomi or sites unprotectable from autonomous spread of the disease in the near future;
• Identify and retain individual trees and understorey plants that appear to be resistant to Phytophthora cinnamomi; and
• Retain the productive potential of the forest should the disease impact remain at low by retaining crop trees.