Abstract: The invention is an engineered wood structure especially well suited to act as large woody debris in stream and lake rehabilitation projects. It is made using a number of small logs, typically about six to ten, assembled into a cylindrical or frustroconical structure. Normally, spaced apart opposing log pairs are joined by spars mortised into them at each end. Adjacent logs may additionally be doweled together at their ends. The spars are sufficiently displaced longitudinally so that they do not interfere spatially with each other although they may be in contact. Radial protrusions may be placed at one end or along the structure to simulate the root wad or limbs of a fallen tree and to provide anchoring when the structure is in place. A central cavity may be filled with rocks to reduce buoyancy and provide further anchoring. The structure can be field assembled in any location using only hand tools.