Manley B FEMC2007

Wood Supply Modelling in New Zealand - Dealing with the challenges

Bruce Manley, New Zealand School of Forestry, University of Canterbury, Private Bag 4800, Christchurch, New Zealand, bruce.manley@canterbury.ac.nz

National and regional wood supply modelling has been routinely carried out in New Zealand since 1969. These forecasts are widely used throughout the forestry sector by decision-makers and planners including company managers, government policy analysts, infrastructure planners and forestry consultants.

The most recent forecasts, completed in 2000, have been criticised as being too optimistic and for presenting too narrow a range of scenarios.
Work has commenced on revised wood availability forecasts. Challenges faced include:
• How to recognise the different quality of information provided by large-scale compared to small-scale owners?
•How to aggregate yield data from a large number of companies and still end up with unbiased estimates of yield?
•What yield regulation assumptions to apply the non-normal estate of small-scale owners?
•How to present results in a way that illustrates the uncertainty associated with company harvest intentions?
This paper describes the methodology that has been developed to deal with these challenges. It also presents examples of how the methodology has been applied.