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Graham West's comment

Last month I commented on the need for good information and professional advice when converting land to forestry. There have been two studies that have looked back at past afforestation eras and calculated how much of that forested area is likely to be harvested at a profit or harvested at all. A study from the University of Canterbury looked at the Whanganui District in 2012 and estimated 5-10% of the forests may never be harvested because of high costs. A second national study by Scion in 2016 for MPI indicated 13% of forests are “highly unlikely” to be harvested based on delivered cost of wood. These studies highlight that understanding how location affects the costs of producing logs is critical to giving land owners advice to plant more trees. The location within a farm affects the amount of roading needed to get logs out to a public road on a truck. Unless the forest block is small and can be harvested in mid-summer, road formation and road metal can cost a minimum of $30,000/km. The location within the landscape is also critical. Contour, slope, and soil type drive harvesting costs. Steep land requires cable harvesting systems that can be twice the cost of flat and rolling terrain. The location in relation to markets or ports affects transport costs. This cost can exceed a quarter of the value of the log. The combination of these factors can make remotely located forests on marginal land uneconomic and may end up costing the forest owner to clear the block