Positioning

Forestry roads, operation trails, harvesting, tending, surface cleanup, and drainage planning are strongly constrained by ground conditions. Slope, wetness, valley terrain, soil depth, spring water, old collapse traces, machine access, and drainage behavior cannot be reduced to a single automatic route or operation result.

This plugin is therefore positioned as a support and record tool for field design. It is most useful after considering a route, operation area, cleanup method, or drainage treatment, then checking where terrain-derived risks overlap with that plan.

How To Read The Results

Use For Harvesting And Tending

The plugin can also support harvesting and stand-tending plans. It should not be used to decide which individual trees to cut by itself. Instead, use it to identify where cutting intensity, yarding routes, cleanup, and slash placement need extra care.

• On steep or unstable slopes, reduce disturbance and check whether cutting or cleanup could trigger windthrow, fallen trees, or soil movement.
• Around valley terrain and wet areas, avoid leaving logs, branches, or slash where they can block or redirect concentrated flow.
• Use flow and wetness layers to plan where bucked logs and branches should be kept along contours, helping slow surface runoff after rainfall.
• Treat Overall Risk as a screening layer for places where harvesting, skidding, and cleanup should be planned more carefully.

Use For Earthwork And Simple Cross Drainage

For forestry operation trails, the plugin can support the placement of small earthwork adjustments and simple cross drainage. It does not design drainage structures automatically. Use it to decide where water should be crossed, dispersed, or kept away from disturbed soil.

• Use Valley Terrain and Flow Estimation to find where concentrated runoff may intersect the trail line.
• Place simple cross drains, rolling dips, or water bars before water gains speed or volume along the trail surface.
• Avoid sending drained water directly into unstable slopes, exposed fill, wet hollows, or existing collapse traces.
• Use Slope Stability and Overall Risk to check where cut-and-fill work should be minimized or handled with extra care.
• Check outlet points on site. The map can show likely water paths, but the actual discharge point must be confirmed in the field.

Recommended Workflow

1. Prepare DEM/DSM data and run the terrain analysis.
2. Draw or import a candidate road/trail alignment based on field knowledge.
3. Overlay the candidate alignment with slope stability, wetness, valley zones, flow, and integrated risk.
4. Mark sections where the alignment crosses valley terrain, wet zones, steep slopes, or overlapping high-risk areas.
5. Confirm those sections on site: soil depth, surface water, spring water, old collapse traces, machine workability, and drainage exits.
6. Record why the alignment was accepted, changed, or rejected.

Limits

• Small springs, buried water paths, soil-layer boundaries, rock, weak fill, and recent disturbance may not appear in DEM-derived results.
• Risk values change when parameters such as friction angle, cohesion, soil depth, rainfall, and thresholds are changed.
• Valley and wetness extraction indicates terrain tendency. It is not a guarantee that water is present or absent.
• Final route judgment should include weather history, planned machinery, construction method, drainage treatment, and maintenance access.

Record Items

When using the plugin output as supporting material, keep the following items with the project or report.

• DEM/DSM source, resolution, date, and processing extent
• Analysis parameters and thresholds used for FS, TWI, flow, and integrated risk
• Candidate route version, date, and reason for route changes
• On-site confirmation points, photos, notes, and GPS tracks if available
• Sections where desktop analysis could not determine the actual condition