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Abstract
When overmature conifers die and deteriorate gradually while standing, a mound of decayed wood builds up about the base of the stem. When such trees fall to the ground, similar material is laid down along the path where the tree fell. Further deterioration results in low mounds or ridges of decayed wood in a state of semi-incorporation with the soil. Depending on the state of decomposition, structure of this organic material may vary from cubical, crumbly yet identifiable wood remains to red-brown masses of finely divided material (fig. 1A).
Citation
Berntsen, Carl M. 1960. Planting sitka spruce and Douglas-fir on decayed wood in coastal Oregon. PNW Old Series Research Notes No. 197, p. 1-5