New Zealand-grown Pinus radiata will be taller and slimmer in the future according to a new paper . While sequestering greater amounts of carbon , the trees will be more exposed to risks from extreme winds and wildfire .

Researchers from Crown research institutes Scion and Manaaki Whenua have considered how climate change and future biosecurity threats might affect New Zealand ’ s plantation forests . Considering the effects of increasing levels of carbon dioxide on photosynthesis , the productivity of radiata pine could increase on average by 10 per cent by 2040 , and double that by 2090 .

Lead author , Scion ’ s Dr Michael Watt explains : “ Increasing

concentrations of carbon dioxide in our atmosphere will increase the rate at which trees grow . An increased growth rate will result in trees becoming taller and more slender .”

This study indicates that the greatest threat to New Zealand ’ s plantation forests is likely to come from increased wind damage as increasingly slender and taller trees will be more susceptible to damage by future wind storms . The risks of breaking or uprooting can be reduced somewhat by modified forestry practices such as timely thinning and earlier harvesting , according to co-author Dr John Moore .

Very high and extreme fire risk days are also predicted to increase ,

with the length of the average fire season increasing by about 70 % by 2040 and 80 % by 2090 . Fire scientist Grant Pearce found the most fire prone regions ( Gisborne , Marlborough , and Canterbury ) will remain the most at risk , but that the relative increase in risk is highest in Wellington and coastal Otago , where it could double and triple to 30 days and 20 days per season , respectively .

New Zealand is currently free of any significant damaging insects , but population levels and damage may increase in the future as warmer temperatures may provide an environment for foreign species and accelerate insect development . Weeds are likely to expand their range under climate change and

compete more strongly with plantations .

“ A decade ’ s worth of research into multiple climate change effects on New Zealand ’ s plantation forests has been summarised here ,” says Michael Watt . “ Determining the magnitude of climate change effects is crucial for informing national economic strategies , forest management and offsetting increasing carbon emissions as the country progresses toward a net carbon zero economy .”