The carbon stored in harvested wood remains sequestered until the wood undergoes combustion or decomposition. However, it is crucial to account for the fossil fuel emissions generated by forestry operations, including harvesting and transportation, to accurately assess the net carbon sequestration of wood products. 

This analysis is essential for understanding the true carbon balance and for the effective implementation of carbon credits and emissions trading schemes

Trees, through the process of photosynthesis, act as natural carbon sinks, sequestering carbon dioxide (CO₂) from the atmosphere and converting it into biomass. This intricate process not only produces oxygen (O₂) as a beneficial by-product but also stores carbon within the wood, roots, and leaves of the tree.

Photosynthesis is the most efficient and cost-effective carbon capture and storage technology available. Mature forests, such as indigenous forests, contain significant carbon reserves within their biomass and soil. In contrast, young, actively growing forests, including commercial plantations, are highly effective at sequestering CO₂, despite having lower overall carbon stocks.

• Fossil fuel greenhouse gases (GHG) emissions in the forestry supply chain are generally between 5% and 10% compared to the carbon content of the roundwood arriving at the mill gate.
• Carbon makes up roughly 25% of the mass of a living tree.
• A Eucalyptus tree harvested at 6/8 years weighs approximately 150-200kg. Its carbon mass is 37.5 - 50kg. 
• 1 ton of carbon (C) converts to 3.67 tons of CO₂.
• An average Eucalyptus tree produces 13.9 kg of O₂ per year. Thus, 53 trees will produce enough oxygen for one person for a year. 
• A pine tree harvested at 18/20 years weighs approximately 250-300kg. Its carbon mass is 62.5 - 75kg.
• 1 hectare of healthy grassland stores approximately 6 tons of carbon in its above-ground biomass
• The 1.2 million hectares of plantations in South Africa have sequestered 203 million tons of carbon dioxide equivalent (tCO₂e) and annually produce timber that contains more than 17 million tCO₂e.
• The annual growth from 157 average Eucalyptus trees can offset the annual emissions from one small passenger vehicle. 

Carbon taxes came into force in South Africa in 2019, set at R 120/ton CO₂e, and are being phased in gradually to allow businesses time to adjust. 

The tax rate is applied per ton of carbon dioxide equivalent (CO₂e) emissions. The carbon tax rate is expected to reach R462/ton by 2030 when forestry and agriculture must commence paying carbon taxes. 

Wood processors like pulp mills, board plants and sawmills are already paying carbon taxes.

The carbon tax framework allows for using carbon offsets, which means that companies can invest in projects that reduce emissions elsewhere in exchange for carbon tax credits. Only carbon offsets originating outside the tax net are eligible to ensure no double-counting of tax benefits occurs. 

Forest biomass derived from deforestation cannot be considered a 'renewable' energy resource. It is only a renewable energy resource when forest productivity is maintained. Hence, the forest continues sequestering carbon over successive rotations.

There is a big difference between energy produced from fossil fuels and biomass. Burning fossil fuels such as coal, oil, and natural gas releases CO₂, which has been locked up on the earth for millions of years. Burning biomass simply returns to the atmosphere the CO₂ absorbed as the plants grew, and there is no net release of CO₂ if the cycle of growth and harvest is sustained. 

Sources: http://www.nature.org http://www.ieabioenergy.com

IETA Carbon Market Business Brief; FSA Environmental Guidelines.

Story by Chris Chapman.