New Zealand relies on fast growing softwood plantations for over 99% of its timber industry. When Europeans first settled New Zealand in 1840, there were impressive native forests which were valued for ships masts and building materials. However, over the next 100 years much of the best forest was cleared for timber, and to make way for farm land. By 1920, forest service officials could foresee a timber shortage, so they began planting fast growing softwood forests.
New Zealand now has 24.9% of its total land area covered by native forest, and 7.7% covered by plantation forest. The forest industry has signed an agreement to protect the native forest, so now only 0.1% of NZ's timber comes from that natural forest.
Softwood plantations of radiata pine, douglas fir and redwood can be grown over a wide range of sites in New Zealand. Softwood plantations have also been grown in the wetter areas of south and east Australia. The timber from these plantations is ideal for solid wood walls. Healthy houses rely on breathable walls which store and release moisture. Softwood can store and release moisture far more quickly than hardwood, and the fast growing sapwood from softwood is more breathable than the heartwood.
Plantation forests are highly productive. Back in 1926 when New Zealand's native forests were at their peak, there were 814,000 cubic metres of sawn timber from natural forests and 19,000 cubic metres from plantation forests. By 2004 natural forests produced 16,000 cubic metres of timber, while the much smaller area of platation forests produced 4,194,000 cubic metres.
New natural forests in New Zealand are estimated to store 5 tonnes of CO2 per hectare per year, while fast growing softwood plantation forests can store over 30 tonnes of CO2 per year. Organicbuilding, by definition only uses wood from plantation forests which are replanted with fast growing softwoods. The forest will then store carbon for another generation of Organicbuilding.