Estimate vegetation height from a lidar dataset

Summary

Estimating vegetation height from a lidar dataset (LAS) can be done using the LAS Point Statistics As Raster tool. However, ground features are identified by classification codes in lidar datasets. Therefore, before estimating vegetation height, ensure the lidar points in the lidar dataset are classified accordingly. For more information on classification codes in lidar datasets, refer to ArcGIS Help: Working with LAS classification in ArcGIS.

As a comparison with other interpolation tools such as the LAS Dataset to Raster (Conversion) tool which interpolates the elevation, the LAS Point Statistics as Raster tool with the Z_RANGE parameter takes into account the elevation of the ground; therefore, it is a relative height which in this case is the height of the vegetation. This is important especially for an uneven ground surface.

Procedure

Information captured by the classified lidar points is essentially height information. By using the LAS Point Statistics As Raster tool, vegetation height can be extracted from the height information captured by the lidar points. The following instructions describe how to use the LAS Point Statistics as Raster tool to quantify, extract, and estimate vegetation height.

Note:
Ensure the lidar dataset ground features are identified and classified with the correct classification codes before using the LAS Point Statistics As Raster tool. 

1. In ArcMap, run the LAS Point Statistics as Raster tool, and define the following parameters:
   • For Method, select Z_RANGE.
   • For Sampling Type, select CELLSIZE.
   • For Sampling Value, use the point spacing distance of the LAS dataset.
2. Click OK. This generates a raster depicting the height of vegetation across the landscape.

Note:
If the survey area contains objects other than vegetation on the ground, remove the height of the other objects, using the land cover raster generated in the Vegetation Coverage Estimation section to limit the analysis to only vegetation covered areas.