Free to Grow Surveys

TimberDrone Advantages


  • A drone can survey about 4 times as many acres per day as a field crew.
  • Improved efficiency means getting more survey acres done in the time allotted.


  • Flying over the terrain is safer than walking through it.
  • Improved safety means fewer accidents and lost work days.

Full Coverage

  • 100% of the area is covered, as oppossed to just the plot centers.

Shareable Data

  • You can share the imagery with others in the office or outside the office.

Permanent Record

  • The imagery serves as a permanent record of how a stand looked at a particular time.

GIS Friendly

  • The imagery is orthorectified and capable of being used in a GIS.
  • All your other GIS layers will line up with the imagery.

How it Works

Free to grow surveys take on two scenarios:

  1. Simple checkoff that says "yes, I've looked it over and this stand is free to grow, no further action is required".
  2. Stocking survey with trees per acre by species.

For scenario 1, it is usually sufficient to fly a low elevation video that covers the majority of the stand.  From the video you can subjectively tell if the stand is sufficiently stocked and no further action is required.  If there is a problem, it is visible in the video and the forester can take action.  In this scenario you would send us ESRI shapefiles or KMLs and we would free-fly the drone over each unit and return a high resolution mp4 file for each unit.  

For scenario 2, it is necessary to generate a 1" resolution orthophoto (see Harvest Unit Depletion section for more details).  When trees reach the free-to-grow stage they are generally large enough to reliably count on an orthophoto with 1" resolution.  We use algorithm based autonomous tree counting to stem map the entire unit.  We also run transects through the unit to collect species and height and apply the percentages to the trees per acre generated from the stem map.

Autonomous Tree Counting

 TimberDrone uses a cloud-based service to count the trees across an entire stand autonomously.  A point shapefile is generated which can be used to generate custom reports.  This is ideal for 5th year surveys as well as post PCT audits.