coarse woody debris
Fallen logs, large branches, and other dead wood on the forest floor — material too large to decompose quickly, persisting for decades or centuries and serving as habitat for fungi, insects, salamanders, and small mammals; as nurse logs for seedlings; as moisture reservoirs; and as slow-release nutrient banks. Coarse woody debris is the forest's savings account — capital accumulated over generations, spent slowly.
Etymology
Forestry and ecology term. "Coarse" distinguishes it from fine woody debris (small twigs and branches). "Debris" from French débris, broken pieces.
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