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Sometimes the wood at the bottom of our woodpile decays to the point where it has only a small fraction of its previous dry mass. What has happened to it? Where did all the carbon go? From the point of view of greenhouse gas emissions, is it better for the wood to be burned in my fire or for it all to rot back into the earth?

Peter Seligman, Victoria, Australia

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This article appeared in print under the headline “Waning woodpile”