Drone mapping provides valuable insights into crop development throughout the growing season. It helps growers and agronomists save time, reduce input costs, and make more informed decisions based on accurate field data.
Sunflower and corn are strategically important crops for many agricultural producers. Their effective cultivation requires regular monitoring, especially for sunflower fields, where each plant can directly influence the final yield.
The Futurology team, DroneUA, was invited to conduct seasonal monitoring of sunflower and corn fields using drones and PIX4Dfields.
The project focused on several key outputs:
- Plant counting.
- Herbicide application planning.
- Growing season analysis.
- Fertilizer application planning.
- Creation of a sunflower flowering map.
Using precision agriculture technology
The fields were surveyed four times at different stages of crop development. Each visit focused on a specific agronomic task and provided data for evaluating crop condition and planning field operations.
Measuring plant counts with drones
The first survey focused on counting sunflower and corn plants and assessing the quality of sowing.
Each sunflower head contributes to the final crop, which may later be processed into sunflower oil. Accurate plant counting therefore provides farmers with important information about crop establishment and potential yield.
The first survey was conducted in early June. The drone captured imagery with a ground sampling distance of approximately 1–2 cm per pixel, providing sufficient detail for identifying individual plants.
The data was processed in PIX4Dfields. A vegetation analysis method developed by the Futurology team was then used to calculate plant coverage with an estimated accuracy of approximately 80–90%.
The resulting plant count enabled the farmer to:
- Assess sowing quality.
- Identify areas with missing or poorly established seedlings.
- Determine the number of sunflower and corn plants.
- Estimate potential yield.
- Prepare harvesting and logistics plans for later in the season.
Planning herbicide application
Drone maps can help avoid unnecessary herbicide application by identifying where treatment is actually required.
The field was surveyed during the tillering and stem growth stages, which occur in the second half of June for sunflower and corn.
At this stage, vegetation height and spatial distribution were analyzed to identify differences in crop development and areas affected by weeds.
The source data was processed in PIX4Dfields and then analyzed further in QGIS.
This workflow produced:
- A weed distribution map.
- A targeted herbicide application plan.
The application map made it possible to treat only affected areas rather than spraying the entire field. This approach reduces chemical use, lowers treatment costs, and supports more environmentally responsible farming practices.
Precision fertilizer application
The Futurology team returned to the fields in early July to prepare a fertilizer application plan for the sunflower and corn crops.
Multispectral imagery was used to assess crop condition by recording reflected light in several spectral bands.
The data was processed in PIX4Dfields to generate an NDVI map. NDVI is sensitive to chlorophyll content and the amount of active plant biomass.
The multispectral imagery was collected using a DJI P4 Multispectral drone.
The analysis was used to create a management zone map showing differences in crop development across the field.
This map supported variable-rate fertilizer planning and helped the farmer:
- Apply nutrients according to actual crop condition.
- Avoid excessive fertilizer use.
- Reduce input costs.
- Improve the return on investment from field treatments.
Flowering stage mapping
At the end of the growing season, sunflower flower heads were counted to assess the stage and uniformity of flowering.
Information about flowering development can be used to plan micronutrient application and other treatments intended to support the crop during the final stages of growth.
A flowering stage map was created in PIX4Dfields to visualize differences across the field and support treatment planning.
Seasonal drone monitoring in agriculture
As a result of the project, the Futurology team provided the customer with actionable information throughout the growing season.
Drone surveys and multispectral photogrammetry helped reduce the use of fertilizer and herbicides while saving time on field inspections.
The farmer also received more accurate information for planning harvest operations and evaluating crop development without damaging plants or interrupting fieldwork.
PIX4Dfields provided the tools required to transform raw aerial imagery into practical agricultural maps. Data collected at different times of the season was used to calculate vegetation indices and compare crop development over time.
Compared with manual inspections or expensive satellite imagery, drones provide detailed and timely information without invasive field measurements.
Project value
The project demonstrated how seasonal drone monitoring can support several agricultural tasks within a single growing cycle:
- Evaluation of sowing quality.
- Plant counting.
- Detection of missing seedlings.
- Weed mapping.
- Targeted herbicide planning.
- Crop condition assessment.
- Variable-rate fertilizer planning.
- Flowering stage analysis.
- Yield and harvest logistics planning.
We thank the Pix4D team for its contribution to the preparation of this use case.
More Pix4D case studies are available through the company’s use case library.
