The forestry industry has many requirements that can be met by a variety of techniques and technologies. As with most industries, these methods have altered over time as new technology and solutions become available. These new options often transform how tasks are completed.
Given the density of foliage that is normally associated with these requirements, laser scanning and Lidar are great options, rather than aerial photogrammetry for example. Depending on the type of asset in question (tree type), the requirements may vary. This could include tree location, tree height, trunk diameter, canopy width, branch locations/ thickness and angle. In some instances, even fruit can be detected via LIDAR (or ground based systems which include photogrammetry).
The Lidar requirement within a forestry application may be for a sample size, where the results are extrapolated across an area or indeed the entire forest may need to be mapped for ‘stock take’ purposes. This certainly requires specific equipment, techniques and experience.
Colorisation is also a popular and a useful aspect used within some of these applications. Often an experienced operator can determine tree type and tree health from the colorized point cloud. This can lead to increased understanding of where water is reaching and where it isn’t. It may also be possible in some instances to monitor weeds via a colorized cloud. In instances where the ground is visible from the sky photogrammetry can also detect certain weed types.
Referring to such things as weeds and moisture content in soil, other technologies exist beyond Lidar and Rgb based Photogrammetry to assist achieve increased understanding. These can include thermal and multi spectral cameras which are certainly well established via available hardware and software.
LIDAR and Drones are increasingly becoming used to provide these solutions for the various forestry industries. This could include a walking LIDAR survey for a test plot. Beyond this, viable options exist to fly drones within the forest or canopy (only viable for test plot applications), and certainly flying a Lidar equipped drone above the canopy is a great solution – often this complements very well, data collected from within/ below the canopy.
For situations where whole forest data is desired this requires a high-end laser scanning solution, flying on a long flight and heavy lift drone, or helicopter, for the purpose of collecting very large areas and possibly entire plantations. This becomes more realistic as technology catches up with the user requirements. Such flying would certainly require BVLOS relaxations if via a drone.