Large woody debris is a term commonly used to describe fallen trees, logs, branches, and other woody materials that accumulate in rivers, streams or in the forest floor. Other useful synonyms for large woody debris include coarse woody debris, dead wood, snags, downed wood and stumpage. These materials are important habitat components that provide shelter and food for aquatic organisms and support ecosystem processes. However, the accumulation of large woody debris can also pose some risks such as blocking navigation channels and causing flooding. Therefore, proper management and monitoring of large woody debris are essential to balance its ecological and social values.