The Problem

The Challenge: A Rapidly Spreading Infestation

In early April 2025, Dunsfield Farms faced a severe outbreak of Fall Armyworm (FAW). As the name implies, the invasive pest was spreading like an army, rapidly ravaging their maize fields during the critical vegetative growth stage. Early signs—pinholes, ragged holes, and skeletonized leaves—were escalating quickly, threatening to wipe out the entire crop.

Without swift intervention, the farm was facing a potential yield loss of over 50%, a catastrophic outcome for their investment.

Why Traditional Methods Failed

Prior methods of combating the infestation were no match for the scale and speed of the outbreak.

• Knapsack Sprayers: Were too slow, labor-intensive, and provided inconsistent coverage across 10 hectares.
• Preventive Measures: Basic, early-season pesticide applications had been insufficient against the intensity of this year’s infestation.

The farm needed a solution that was not only powerful but also incredibly fast and precise.

Our Solution

Our Solution: A Two-Stage Aerial Intervention

We deployed a data-driven strategy combining multispectral analysis for diagnosis and precision drone spraying for treatment.

Stage 1: Diagnosis with a Multispectral Drone

First, we conducted an aerial survey using the DJI Mavic 3 Multispectral drone to accurately assess the extent and severity of the damage. While standard visual (RGB) images show obvious damage, multispectral sensors detect subtle stress in plants that is invisible to the naked eye.

The NDRE Advantage: We analyzed the field using two different vegetation indices: NDVI and NDRE. While NDVI is a common metric for plant health, it can be misleading in mature crops. Our analysis showed that the Normalized Difference Red Edge (NDRE) index provided a far more accurate picture of the FAW damage. NDRE is more sensitive to chlorophyll variation and can detect stress before it becomes visually apparent.

This deeper insight allowed us to create a highly accurate "prescription map" for the spraying operation, ensuring no pesticide was wasted and every affected area was targeted.

Stage 2: Treatment with Precision Spraying

Using the insights from the NDRE prescription map, we deployed the DJI Agras T50 drone for the insecticide application. This method offered three key advantages:

• Speed: The entire 10-hectare field was treated in a fraction of the time manual labor would take.
• Uniformity: The drone ensured consistent, uniform coverage across every plant.
• Safety: It eliminated the need for farm workers to have direct exposure to harmful pesticides.