How to collect ground truth images

How to collect ground truth images

Ground truthing is an important part of the field survey. Good collected ground truth means more accurate analysis results. Ground truth is very important for detection of specific phenomena such as weeds, disease, pests, stress…

What is the ground truth?

Ground truth is a method of collecting digital information about the condition of the crop and field in general.

How can I collect good ground data?

Best way to collect ground truth is to put a marker on phenomena you want to detect and take a picture from above with a mobile device. Placing a marker will allow you to find that position on a map and mark it with a location tool on Agremo app. When you mark the desired position on the map with the location tool, a pop up window will appear. Now you can enter a title, comment and upload a picture you take on a field. 

You can mark bad parts of the field as well as good parts of the field

Types of markers:

1×1 meter square marker (Made of PVC ducts)


1×1 meter square marker (Made of PVC pipes)


Circle marker (hoop)

Or any other type of marker


Or any other type of marking the phenomena which will be noticeable on map.

NOTE: The width of of the marker should be twice as GSD.

When you need to ground truth orchids, you can take an image with your drone.







Also, you can take an image and mark the geolocation (with a geolocation apparatus or with a geolocation application ) of the place where the image was taken. Then you can find that geolocation directly on the Agremo app.

TIPS: The width of the PVC pipes or ducts for square markers should be twice as wide as the target GSD (at least 5 cm or 2 in). This also applies to the hoop-shaped marker.
When crops are in later growing stages PVC markers with stands are needed.


What Our Clients Say About Us

  • After introducing mapping and crop analysis reports to farmers, they could see their field from another perspective. Agremo is helping us bring essential information to farmers which were impossible to get until recently.

    Ramón Pagán

    Mapping Expert and President @ Caribe Drones // Puerto Rico

  • Agremo’s map is more specific. Competitors break their maps into half-acre grids, but Agremo colors the whole thing exactly how it is. Visually, it’s night and day. A lot of farmers are visual.

    Corey Nohl

    Drone Operator and Farmer @ Above All Aerial // MN, USA

  • With Agremo reports, farmers they can increase productivity, reduce major problems by having early warnings during the early stages of the crops preventing major losses. Bottom line, increase ROI while minimizing losses.

    Miguel Ángel Salgado

    General Manager & Mapping Expert @ Ansar Drone // Mexico

  • The best thing about the plant population reports is the accuracy, which is splendid and it is very important! Great service at eye level with the customer!

    Sune Enevoldsen

    Field Manager and Drone Operator @ Noble Nordmann // Denmark

  • The biggest benefit for farmers who use drones and Agremo reports is that they increase their yields, reduce costs or improve their productivity. In the end, all these benefits are lead to extra profits.

    Ciprian Iorga

    General Manager @ La Orizont // Romania

  • We introduced new farming methods to farmers in Africa, who recognized that Agremo and drones can provide them with quicker, more convenient, efficient and accurate way of gathering decision making information.

    Derrick Annan

    CEO @ Aeroshutter // Ghana

  • With Agremo, we doubled our productivity, and our forestry clients are happy with the Agremo reports necessary for the inventory system as well as a stem map with tree distribution.

    Curt Rogers

    Co-owner @ TimberDrone // USA

  • Of the few vendors who advertised drone imagery analytics, Agremo provided a vastly superior capability. It is extremely important to base any remote sensing assessment in solid ground truth. Agremo clearly excelled over their competitors.

    Konrad Kern

    Image Scientist @ Falcon Aerial Data // USA

  • Agremo Stand Count Analysis shows how successful seeding was and how many plants farmers will be able to harvest. Withal, it can help to apply different sowing standards in different parts of the plot, in order to achieve the highest yields.

    Zdravko Hojka

    Agroservice and Product Manager (Maize and Oil Crops), KWS SAAT AG

  • Since we ran our first report with Agremo, both our company and our customers continue to be impressed with the accuracy of the reports compared to our ground truthing. We have leveraged many Agremo reports but find the most value in crop health, weed and stand count analyses. We continue to leverage the Agremo intelligence as a proven way to improve our customers’ bottom line.

    Jeff Buyck

    VP of Precision Ag C&B


    No credit card required