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 65 rotting logs DHJanzen100303.jpg high resolution
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| This tropical Maclura tinctoria (Moraceae) log, down on the forest floor for several years, shows clearly the differential rotting of sapwood and heartwood. The yellow heartwood is rockhard and essentially untouched by decomposers. The sapwood (which was a clear ivory color when the tree was newly cut) is now soft, pulpy and fungus and insect riddled, and will be gone within a few more years - while the heart wood will last for decades as the rainwater gradually leaches out its secondary compounds, making it consumable by litter decomposers. These secondary compounds move into the ground water and into stream runoff, where they are part of the organic carbon eventually consumed by aquatic microbes. | ||
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