Log Erosion Barrier (Contour Log Felling)
What – Logs are partially entrenched or/and staked to soil surface parallel to the contour.
Purpose – Intended to slow runoff, cause localized ponding, and capture and store eroded sediment when arranged in a bricklayer pattern on hillslopes.
Effectiveness – Studies indicated that log erosion barriers may reduce runoff, peak flows, and sediment yields for low intensity rain events (< 1.8” per hour), but are unlikely to have a significant effect for high intensity rain events. Sediment storage was reported to decrease by 10–15% with each successive rain event. Although the potential volume of sediment stored is dependent on slope, tree size and length, frequency, and use of berm traps, with proper implementation effective sediment storage and creation of microsites can be achieved.
Please note: some agencies, such as the US Forest Service, no longer endorse this method. However, other users have reported success with this method when logs are properly placed and secured. Please consider the cost, ease of application, and safety, and consult with experts in the post-fire treatment profession who can provide perspective, insight, guidance, and advice in an ever evolving field of practice.
Where
- Hillslopes with high- and moderate-burn severity.
- Slopes between 25 and 60 percent.
- Soils with high erosion-hazard ratings.
- Watersheds with high values at risk.
Cost – $420–1200 per acre. Additional factors include:
- Terrain
- Site access
- Frequency of logs
- Labor experience
How to Links – See USDA BAER Catalog page 45 (PDF page 53); and NRCS Log Erosion Barriers Fact Sheet.