Wood availability forecasting in New Zealand - meeting the challenges

Forecasts of wood availability from New Zealand plantations have been undertaken regularly since 1969. The latest round, completed in 2010, differs in approach from previous forecasts in terms of model structure, adjustment to data and constraints. Large-scale owners were differentiated from small-scale owners with the area of the latter reduced by 15 per cent. Yield tables were calibrated using harvest intentions of large-scale owners. Four different yield regulation strategies were modelled including a scenario in which yield was required to be non-declining only for the current rotation. This matches the non-normal age-class distribution of the small-scale owners' forest estate - a consequence of large areas of afforestation in the 1990s. Plans are under way for the next forecasting exercise. A similar approach to the 2010 forecasts is likely to be adopted, but with an effort to verify areas and yields for the small-scale estate. Forecasts are of physical wood availability - a separate analysis of the economic wood availability may be undertaken to complement these forecasts