Cut the woods. Keep them connected.
Dendritic Forest Management checks a harvest plan against the corridors that link your old-growth candidates, stream cores and reserves. If a unit breaks a link, the check names the unit and draws the break on the map before anyone starts a saw.
One question, asked before every harvest
Do the core areas stay linked by retained forest at least the minimum width, before and after the planned treatment units?
Pass links hold
Every core area linked today is still linked after the plan, and no unit enters a corridor without a recorded light-treatment permission.
Fail a link breaks
A unit cuts a corridor, narrows it below the minimum width, clears a core, or enters retained forest unpermitted. The check names each unit responsible and maps the lost corridor.
Incomplete inputs missing
A layer is missing, a geometry is wrong, or no source is recorded for the minimum width. The check never reports a pass it could not establish.
How the check works
Map what is there. Core areas, retained corridors along streams and between stands, roads, open water and road crossings, each with its source.
Set the minimum width. A site parameter in meters, with a recorded reason such as a co-op policy or a forester's recommendation.
Remove what interrupts forest. Road surfaces and open water come out. A road keeps a corridor only where a crossing is recorded on it, and an assumed crossing is flagged for field checking.
Draw in the plan. Each treatment unit comes out of the forest unless it is a recorded light treatment, such as single-tree selection with a stated reason.
Test every link. Two cores are linked when a strip of forest the minimum width runs all the way between them. Links present today but missing after the plan fail the check.
Every result records the engine version and a checksum of its inputs, so the same inputs always give the same answer.
Three ways to use it
In a VergeCommon co-op
Woodland projects are being tested in VergeCommon and are not yet open to co-ops. In them, stewards review the corridor layers, every member's harvest plan is checked before it can be reviewed, and a plan that breaks a link needs a recorded member vote.
In the mapping workspace
Draw or import roads, streams, cores, crossings and treatment units, run the check, and download a Landscape Package to share with your co-op or forester.
In your own software
The check is a small JavaScript package with no server or storage. Give it GeoJSON; get back pass, fail or incomplete with reasons.
What a pass does and does not tell you
- It establishes
- That mapped retained forest of at least the minimum width connects the same core areas after the plan as before, given the layers and crossings as recorded.
- It does not establish
- That wildlife moves through the corridor, that populations stay genetically viable, that a stand is old growth, or that a plan meets any regulation. Those need field evidence and qualified review.
- Old growth
- Mapping alone makes a stand an old-growth candidate. Calling it old growth requires field evidence of its structure, reviewed by someone other than the person who mapped it.
- Distances
- Horizontal, on a spherical Earth, within about half a percent. Slope and edge effects are not modeled.
Built in the open
The method, the code and the research toolkit are on GitHub under the MIT license. The research toolkit explores dendritic network theory and is marked experimental; the corridor check does not depend on it.
Help us find where it is wrong
Foresters, ecologists and developers: test the check on a woodlot you know, review the method, or take an issue. Reports of a wrong answer are the most useful contribution there is.