Averaging accounting became the new default carbon accounting system for production forests in 2023. Under averaging accounting, first rotation trees earn carbon credits up to their "average age" (16 to 26 years, depending on species - see table below). These carbon credits do not have to be surrendered when the trees are harvested, provided the forest is replanted within four years of harvesting. Other key points to note about averaging accounting:
Stock change accounting was the default carbon accounting system before 2023. Under stock change accounting, trees earn carbon credits up to at least age 50 and potentially beyond. Depending on the age of the trees and the year they were registered in the ETS, most, if not all, of these carbon credits have to be surrendered again when the trees are harvested. Other key points to note about stock change accounting: