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Channel Clearing: Removal of woody debris firm channels by heavy equipment or cable yarding. Channel Loading: Sediment inputs into ephemeral or perennial stream channels. Check Dam: Small structure in zero or first order channels made of rocks, logs, plant materials, or geotextile fabric designed to stabilize the channel gradient and store a small amount of sediment. Contour-Felled Logs: System for detaining runoff and sediment on elopes by felling standing tim- ber (snags) along the contour, delimbing and anchoring the loge, and backfilling to create small detention basins. Also known as contour- felling,contour log ten•aces, log erosion barriers (LEB s). In some regions, contour-felling describes only felling the standing timber in the direction of the contour but not anchoring or backfilling. Contour Furrowing: See Contour Trenching. Contour Trenching: Construction of trenches on elope contours to detain water and sediment transported by water or gravity downslope generally constructed with light equipment. These are also known as contour terraces or contour furrowing. Cross Drain: A ditch relief culvert or other structure or shaping of a road surface designed to capture and remove surface water flow. Culvert Overflow: Specially designed sections of roadway that allow for overflow of relief cul- verts or cross-drain culverts without compro- mising the integrity of the road surface. Culvert Riser: Vertical extension of culvert on the uphill aide to create a small pond for detaining sediment. Culvert Upgrading: Replacing existing culverts with large diameter ones. May also include armoring of inlet and outlet areas. Debris Avalanche: Mass failure of variably sized elope segments characterized by the rapid downhill movement of soil and underlying geologic parent material. Debris Basin: Specially engineered and constructed basin for storing large amounts of sediment moving in an ephemeral stream channel. Debris Clearing: See Channel Clearing. Design Storm: Estimate of rainfall amount and duration over a particular drainage area. Often used in conjunction with the design storm return period, which is the average number of years within which a given hydrological event is equaled or exceeded (i.e., 5-year return period). Ditch Maintenance: Various maintenance activi- ties to maintain or restore the capacity of ditches to transport water. Activities include sediment and woody debris removal, reshap- ing, and armoring. Dry Ravel: Downhill movement of loose soil and rock material under the influence of gravity and freeze-thaw processes. Ephemeral Stream or Channel: Drainage way which carries surface water flow only after storm events or snow melt. Energy Dissipater: Rock, concrete, or impervious material structure which absorbs and reduces the impact of falling water. Erosion: Detachment and transport of mineral soil particles by water, wind, or gravity Fire Intensity: Rate at which fire is producing thermal energy in the fuel-climate environ- ment in terms of temperature, heat yield per unit mass of fuel, and heat load per unit area. Fire Severity: See Burn Severity. Forb: Aerbaceoua plant other than grasses or grass- like plants. Gabion: A woven galvanized wire basket sometimes lined withgeotextileaandfilled withrock,stacked or placed to form an erosion resistant structure. Geotextile (Geowebbing): Fabric, mesh, net, etc. made of woven synthetic or natural materials used to separate soil from engineering mate• rial (rocks) and add strength to a structure. Grade Stabilizer: Structure made of rocks, loge, or plantmaterial installed in ephemeral channels at the grade of the channel to prevent downcutting. Ground Seeding: See Seeding. Hand Trenching: Contour trenching done manually rather than mechanically. Hydrophobic Soil: See Water Repellency. In-channel Felling: Felling of snags and trees into stream channel to provide additional woody debris for trapping sediment. Intlltration; Movement of rainfall into litter and the soil mantle. Lateral Keying: Construction or insertion of log or rock check dam 1.5 to 3 ft (0.4 to 1,0 m) into stream or ephemeral channel banks. Log Check Dam: See Check Dam. Log Erosion Barriers (LEBS): aeeConfour-Felled Logs. Log Terraces: See Contour-Felled Logs. Mass Wasting: Movement of large amounts of soil and geologic material downalope by debris avalanches, soil creep, or rotational slumps. Mg ha t: Metric ton per hectare or megagram per hectare, equivalent to 0.46 tons per acre (0.45 t ac 1). Monitoring: The collection of information to deter- mine effects ofresoun:emanagement or specific treatments, used to identify changing condi- tions or needs. Monitoring, Compliance: Monitoring done to assure compliance with Best Management Practices. USDA Forest Service Gen. Tech. Rep. RMRS-GTRE3. 2000