The Seen and Unseen World of the Fallen Tree

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Full Issue

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Large fallen trees in various stages of decay contribute much-needed diversity to terrestrial and aquatic habitats in unmanaged old-growth Douglas fir forests. When most biological activity in soil is limited by low moisture availability in summer, the interface between soil and a fallen tree offers a relatively cool, moist habitat for small animals and substrate for microbial and root activity. Increased utilization and management can deprive future stands of large fallen trees and smaller woody debris. Visible and invisible stages in the decay of fallen trees are discussed to encourage awareness of the losses in habitat diversity and long-term site productivity that may result from increased removal of woody debris from streams and forests in the name of economic progress.


This item was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.