How to use

FLM can be opened by running the included .py script or .bat file. The latter automatically detects and uses the latest available version of Python. Upon opening one of these files the user should see a command prompt window as well as a graphical user interface (GUI; Figure 1).

Figure 1. FLM graphical user interface (GUI) with tools enumerated in sequential order as they would be normally used. Main tools (1, 2, 3 and 4) are numbered in green and connected with arrows. Optional tools (0, 2.5a, 2.5b, 3a, 3b and 5) are numbered in gray. Output center lines are obtained in tool 2, output footprint polygons are obtained in tool 3. Lines receive attributes in tool 4. Tools 3a and 3b serve as alternatives to step 3.

There are currently five main categories of tools included in the FLM package: pre-processing, mapping, attribution, auxiliary and alternative. Mapping and attribution are the main steps, pre-processing, auxiliary and alternative are the optional steps outlined in Figure 1. Specific tool descriptions, inputs and outputs are outlined in the documentation section of this guide.

FLM tools require ESRI ArcGIS Pro to be installed with the Spatial Analyst extension in order to run. ArcMap is no longer supported by FLM.

Main Inputs

Figure 2. Example study area displayed as an RGB orthophoto.
Figure 3. Example inputs for the study area: a canopy height model raster image and large-scale forest line polylines.

Main Outputs

Figure 4. Example outputs for the study area: corrected, small-scale center lines and areal footprint polygons for the forest lines.


To get good result out FLM tools, the quality of the input lines is critical. There are two tools: Pre-tagging and Vertex Optimization to help to batch pre-processing input lines and make them more suitable for other tools' input

Figure 4. Method for optimizing vertices.

Line Attributes

Once mapped with FLM tools, forest lines can receive attributes which relate to their spatial properties. Additional information may allow for greater insight on forest line conditions. FLM provides a series of standard line attributes as well as the capability of deriving attributes from external data provided by the user. Table 1 provides some examples of standard attributes and a full list of currently supported attributes is available in the documentation section of this guide.

Table 1. Examples of information types provided by FLM default attributes.
Average Width Sinuosity Fragmentation Micro-topography
... ... ... ...

Mapping Workflow



The scripts included in this toolset make use of multiprocessing to split the task of mapping and attributing lines into multiple parallel processes. This factor allows several CPU cores to work at once dramatically reducing the processing time on extensive application areas. By default the maximum number of available cores is used by the FLM. This is usually desirable to process large inputs faster, but may temporarily slow down other processes in the computer. If the user wishes to specify the number cores to be used by FLM tools they can find this option within the user interface.

Temporary Files

All subfolders within the Scripts folder are temporary workspaces. These are used to store temporary files which are automatically deleted upon the end of execution. While running FLM tools make sure that files in the temporary folders are not opened in ArcGIS, as this will place a "lock" in these files preventing them from being edited by the FLM. To make sure that there are no locks affecting the tools, clean the temporary folders or delete the folders themselves before running the FLM.