Glossary
Anabranching channel: A stream or river that has two or more channels at bankfull or effective discharge flow. Unlike braided channels, anabranching channels are separated by vegetated islands. While a braided channel becomes a single wide channel at bankfull flow, anabranching channels still retain multiple channels. Generally this term is synonymous with anastomosing. (Source: 2016 National Large Wood Manual)
Braided streams: Wide shallow channels with multiple unvegetated bars. At low flows they have multiple channel threads, but at a bankfull or effective
discharge the bars are submerged and flows coalesce to form a single channel. Braided channels form in areas with high sediment supplies and relatively steep gradients, such as downstream of alpine glaciers. The multiple channels of braided streams tend to be shallow and wide as opposed to the narrow and deep channels of ananabranching or anastomosing channel. (Source: 2016 National Large Wood Manual)
Cable: Steel aircraft cable or wire rope used to secure large wood. (Source: 2016 National Large Wood Manual)
Check dam: A small dam constructed to slow stream velocity and/or prevent degradation. (Source: 2016 National Large Wood Manual)
Debris: Fragments of solid matter, typically rock or organic material found moving down a river. Commonly has a negative connotation synonymous with “refuse” or “garbage” that concerns some people when using it to describe natural materials found in rivers; therefore, “debris” is increasingly being replaced by “material” when referring to wood. (Source: 2016 National Large Wood Manual)
Ecological Trajectory: The developmental pathway of an ecosystem through time. (Source: SER Primer on Ecological Restoration)
Engineered Log Jams: General term referring to a human designed and constructed structure of inter-locking logs intended to emulate natural logjams
using scientific and engineering data to determine appropriate placement, materials, architecture, and size to ensure the stability and function that will achieve project goals. There is no single type of engineered log jam, and structures can vary significantly in shape, architecture, size, and function. (Source: 2016 National Large Wood Manual)
Grade control/grade stabilization structures: Techniques used to stop channel degradation, typically accomplished by the construction of in-channel structures. (Source: 2016 National Large Wood Manual)
Hyraulic control structure: A type of grade control structure designed to reduce the energy slope along the degradational zone to the degree that the stream can no longer scour the bed. (Source: 2016 National Large Wood Manual)
Hyporheic zone: A region beneath and alongside a stream bed, where there is mixing of shallow groundwater and surface water. The flow dynamics and behavior in this zone (termed hyporheic flow or underflow) is recognized to be important for surface water/groundwater interactions, as well as fish spawning, among other processes. As an innovative urban water management practice, the hyporheic zone can be designed by engineers and actively managed for improvements in both water quality and riparian habitat. (Source: 2016 National Large Wood Manual)
Log vanes/step jams: Single logs or small bundles of logs secured to bed. Also called log bendway weirs (if partially spanning channel and angling upstream) or log steps (if fully spanning channel, and usually placed perpendicular to channel). (Source: 2016 National Large Wood Manual)
Log weirs/valley jams: Weir-like accumulations built around one or more large logs (key members). (Source: 2016 National Large Wood Manual)
Post: Similar to a pile but placed by excavating a hole, placing the post, and backfilling. Excavated holes are necessary to bury a tree with attached rootwad—an element that has significantly more resistance to pulling out or overturning than a pile driven to the same depth. (Source: 2016 National Large Wood Manual)
Rootwad revetments: Use of locally available logs and root fans to add physical habitat to streams in the form of coarse woody debris and deep scour pockets. (Source: 2016 National Large Wood Manual)
Salmonid: Family of fish that includes salmon, trout, and char. All of the species breed in freshwater, are migratory, and spend part of their life cycle in the ocean. (Source: 2016 National Large Wood Manual)
Snags: Dead trees that are left upright to decompose naturally. (Source: National Wildlife Federation)
Vanes: Flow-changing structures constructed in the stream designed to redirect flow by changing the rotational eddies normally associated with streamflow. They are used extensively as part of natural stream restoration efforts to improve instream habitat. (Source: 2016 National Large Wood Manual)
Wattle: A soil bioengineering technique made up of rows of live stakes or poles with live plant materials woven in a basket-like fashion. A wattle fence can be used to deter erosion in ditches or in small dry channel beds to resist the formation of rills and gullies. (Source: 2016 National Large Wood Manual)
Links, Publications
National Large Wood Manual: Assessment, Planning, Design, and Maintenance of Large Wood in Fluvial Ecosystems: Restoring Process, Function, and Structure (final, PDF, 32.1MB) By David J. Bandrowski (R.J. Wittler)
Chin, Anne & Daniels, Melinda & Urban, Michael & Piégay, Hervé & Gregory, K & Bigler, Wendy & Butt, Anya & L Grable, Judith & Gregory, Stanley & Lafrenz, Martin & R Laurencio, Laura & Wohl, Ellen. (2008). Perceptions of Wood in Rivers and Challenges for Stream Restoration in the United States. Environmental management. 41. 893-903. 10.1007/s00267-008-9075-9.
Cluer, Brian & Thorne, Colin. (2014). A Stream Evolution Model Integrating Habitat and Ecosystem Benefits. River Research and Applications. 30. 10.1002/rra.2631.
Collins, B. D., D. R. Montgomery, K. L. Fetherston, and T. B. Abbe. 2012. The Floodplain Large-Wood Cycle Hypothesis: A Mechanism for the Physical and Biotic Structuring of Temperate Forested Alluvial Valleys in the North Pacific Coastal Ecoregion. Geomorphology 139/140:460–470
Lininger, Katherine & Wohl, Ellen & Sutfin, Nicholas & Rose, Joshua. (2016). Floodplain downed wood volumes: A comparison across three biomes. Earth Surface Processes and Landforms. 10.1002/esp.4072.
Livers B, Wohl E (2017) Historical land use as a driver of alternative states for stream form and function in forested mountain watersheds of the Southern Rocky Mountains. Earth Surf Process Landf. https://doi.org/10.1002/esp.4275
Montgomery, D.R., Collins, B.D., Buffington, J.M., Abbe, T.B., 2003a. Geomorphic effects of wood in rivers. Gregory, S.V., Boyer, K.L., Gurnell, A.M. (Eds.), The Ecology and Management of Wood in World Rivers. American Fisheries Society Symposium 37, American Fisheries Society, Bethesda, MD, pp. 21-48.
Scott, Daniel & Wohl, Ellen. (2018). Natural and Anthropogenic Controls on Wood Loads in River Corridors of the Rocky, Cascade, and Olympic Mountains, USA. Water Resources Research. 10.1029/2018WR022754.
Sedell, James R.; Luchessa, Karen J. 1982 . Using the historical record as an aid to salmonid habitat enhancement. In : Armantrout, Neil B., ed. Proceedings of the symposium on acquisition and utilization of aquatic habitat inventory information; Portland, OR. Bethesda, MD: American Fisheries Society, Western Division: 210-223.
Wohl, Ellen & Hall, Robert & Lininger, Katherine & Sutfin, Nicholas & Walters, David. (2017). Carbon dynamics of river corridors and the effects of human alterations. Ecological Monographs. 10.1002/ecm.1261.
Wohl, Ellen & Lininger, Katherine & Scott, Daniel. (2017). River beads as a conceptual framework for building carbon storage and resilience to extreme climate events into river management. Biogeochemistry. 10.1007/s10533-017-0397-7.
Ellen Wohl, Daniel N. Scott and Katherine B. Lininger, Spatial Distribution of Channel and Floodplain Large Wood in Forested River Corridors of the Northern Rockies, Water Resources Research, 54, 10, (7879-7892), (2018).
Wohl, Ellen. Of wood and rivers: bridging the perception gap. WIREs Water 2015, 2: 167-176. doi: 10.1002/wat2.1076
Wohl, E. 2013. Floodplains and Wood. Earth-Science Reviews 123:194–212.