Measuring tree carbon

How tree carbon is calculated

One of the most valuable functions of trees and other vegetation is that they absorb carbon dioxide from the atmosphere and release oxygen. Trees store carbon for long periods in their roots, trunks, branches and leaves and it is generally accepted that approximately half the dry weight of any tree is carbon.

Mitigating the effects of climate change

The consensus among climate scientists and other experts is that trees play an integral role in mitigating the harmful affects of global warming and climate change.

Large old trees store the most carbon but newly planted trees will tend to grow comparatively quickly and will therefore absorb more carbon dioxide than trees that are mature or senescing (have reached later maturity; are growing old). Stored carbon is released into the atmosphere as the tree grows and eventually dies or when it falls or is cut down and then rots and decomposes.

The amount of carbon stored in a tree is approximately half its total biomass and by multiplying this figure by 3.67 you are able to estimate how many kilograms of carbon dioxide that represents.

Tree carbon calculation

The table below provides some figures relating to the circumferences of trees, the amount of carbon stored in kilograms and the approximate amount of carbon dioxide they typically absorb. These figures are only approximate as all trees vary in their rate of growth, depending on species, location, soil, temperature and other climatic factors.

These figures relate to hardwood species which grow at a relatively constant rate throughout their lifespan, with only minor fluctuations throughout the growth period. The majority of Australian native trees would fall into this category.

Circumference (cm)Carbon stored (kg)Co2 absorbed (kg)
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