Resilient forest design – a new approach

Authors: Graham West
Publication: New Zealand Journal of Forestry, Volume N.Z.J.For. 2025, Issue N.Z.J.For. 70(2) 2025, pp Pages 23-28, Aug 2025
Publisher: New Zealand Institute of Forestry

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Abstract: To help improve resilience in forest growing, a change to the approach, measurement and terminology used to quantify resilient forest design is proposed. A broader range of criteria for evaluating risks by sites, species and management regimes is suggested. These need to be quantitative and derived from a greater understanding of site and tree crop ecological and mechanical limits. As an example, for a given site, species and management regime, the critical threshold values for many risk factors could be calculated (e.g. wind speed, soil water saturation, soil moisture deficient or disease susceptibility). The threshold could be when unacceptable losses in the forest crop occur. For this approach to work, a multi-factor quantitative approach is needed to replace qualitative rules using subjective risk levels. Resilience also means financial survival and this incorporates market resilience, social licence to operate and government policy support. Designing for greater resilience requires stronger sector collaboration that leads to more rapid adaptation. It is important to agree on how to measure resilience, what risk factors should be included, and what are the priorities by site type. A transition strategy may be needed to diversify the existing forest estates from being heavily dependent on one species, one export market and one management regime. Regardless of what is changed in the short term, long-term markets for 20 million tonnes/yr of radiata pine export grade logs will be required for at least the next 20 years. Radical new uses of wood are needed to provide higher returns that compensate for rapid increases in growing and harvesting costs. Value chain agility is required as uncertainty is likely to continue. Science projects that provide quick answers are needed to moderate increasing regulatory land-use intervention. A broader science programme is needed than is currently supported by government or industry. This will require more stakeholder involvement, a multi-CRI approach, and possibly international collaboration. A pragmatic way forward to break the problem into three phases is suggested: To create a baseline, estimate with local knowledge the levels of resilience for a complete range of critical risk factors. This will need to consider site types and species groups. Spatially simulate with the best available science the high priority factors and gaps. Broaden the current programme of empirical science to test major assumptions and validate models. Forest management requires pragmatic strategic decisions to be made each year on species choice and tending regime. To help with this an evaluation matrix has been developed in Excel. Using a broad range of risk factors, making estimates of resilience will highlight knowledge gaps and where to engage experts. The strategic, spatial and mechanical nature of the resilience problem requires critical thinking and multi-disciplinary application. Radical collaboration between stakeholders is very important if we are to achieve rapid progress to adapt and mitigate the unpredictable future that forest growing is facing.

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