He also said a cross-party group of MPs under Globe NZ'had recently launched a report they had commissioned the London firm of Vivid Economics to undertake.
"The over-arching message delivered by the Vivid consultants is that if we aren't prepared to consider land-use change as part of our toolbox for meeting climate change goals then we are not going to make it," Mr Rhodes said. "This does not mean the authors are suggesting shooting cows and blanketing the hillsides with pines as some have suggested. It is all about the right trees, in the right places. Typically not all of the farm, not always radiata and not always all for production."
Landowners would need support to achieve growth in plantation trees on a scale that the Vivid report suggests, which is between 1 and 1.6 million hectares by 2050.
Growth of 1.6 million hectares would nearly double the size of New Zealand's plantation forests in a little over 30 years from now, although even this would still only be around 10 per cent of New Zealand's total land area. Mr Rhodes said Northland had much land, including Maori land, that was unproductive or low producing for drystock farming, but highly suitable for trees.
Northland contributes 10 per cent of national forestry GDP and is the third biggest forestry area in New Zealand. Despite this, processing plants in Northland are facing a reduction in wood supply in about 8-10 years that will likely see processing capacity decline. Large-scale new planting now was probably too late to fully meet the looming shortfall, but would at least restore some confidence to the most competitive processing plants to see through the supply trough and come out the other side.
With cross-party support for the Vivid proposals as a sign of parliamentary endorsement, Mr Rhodes said he anticipated we would need to be gearing up for large planting increases very soon.
"I would warn that the nursery industry will need time to expand to meet the targets. Seed supplies are available but nurseries will need to gear up," he said.
Access to labour would be the biggest constraint, Mr Rhodes predicted.
"Industry training organisations need to learn to work in a co-operative and efficient way and we need greater flexibility in TEC funding to ensure the effective delivery of relevant training into the forest industry," he said.
"We may also need an RSE [Recognised Seasonal Employer] scheme specifically designed for forestry silviculture workers. That's one of the ways in which we need government assistance. A ministry or at least a dedicated department within MPI focused on forestry would also be welcomed."
Mr Rhodes said the other major issue in Northland was the rural roading network.
"With small towns and a limited pool of ratepayers to meet the local share of upgrades across a massive rural road network, I'd suggest the current funding model is broken. Alternatives need to be researched and acted on urgently."