Soybean herbicide reduction is critical for managing weeds in soybean production. Weeds in the USA and Canada, if left uncontrolled, can cause yield losses of up to 49–52% (Weed Science Society of America). Particularly problematic are waterhemp (Amaranthus tuberculatus) and pigweed (Palmer amaranth), whose seasonal interference can reduce soybean yield by 44–56%, with extreme cases exceeding 70% losses. Over the past decade, the spread of these aggressive weeds has become a significant issue for soybean farmers in the USA.
Precision agriculture solutions, such as drone-based weed mapping and targeted spraying, offer an effective strategy to manage weeds. By integrating high-resolution drone imagery with variable-rate spraying, farmers can reduce herbicide costs, protect crop yield, and minimize long-term risks from uncontrolled weed growth.
Brillhart Farms – Soybean Weed Control Field Story
Brillhart Farms was facing significant weed challenges in their soybean fields, including pigweed, waterhemp, and foxtail. Traditional blanket spraying of the entire field would have led to unnecessary herbicide costs, potential crop damage, and reduced soybean yield. This risk is particularly high with certain herbicides, such as glufosinate (Liberty), which can harm soybean blooms and further impact overall production.
Precision Spraying for Soybean Herbicide Reduction
To avoid unnecessary herbicide use and crop damage, Brillhart Farms implemented a precision weed management strategy:
Mapping and Weed Detection
- Using Agremo Weed Analysis, the team performed detailed weed mapping in a “green-on-green” scenario — a unique solution that detects weeds even within dense soybean canopies — using data collected by the DJI M3M
Creating a Variable-Rate Spraying Map
- The Agremo Spraying Tool then automatically generated a variable-rate spraying map with two zones: the system applied full herbicide dosage to areas with detected weeds, while leaving weed-free areas unsprayed, reducing chemical use and protecting the crop.
Targeted Spraying for Soybean Herbicide Reduction
- The DJI Agras T40 drone executed targeted spraying, flying 8 feet above the canopy at 25 ft/sec. Its smaller liquid volume in the tank allowed longer flight times per battery, and the drone sprayed only where needed.
Soybean Herbicide Savings: Practical Results and Benefits
Out of a total of 50 acres, only 13.55 acres were treated. This resulted in:
- 73% reduction in area requiring spraying,
- $250 saved on herbicide costs,
- $450 additional savings from prevented yield loss (avoiding crop damage from ground sprayers),
- Over $600 in immediate savings were achieved in just a few hours of drone operation.
Moreover, targeted spraying prevented unnecessary exposure of soybean plants to glufosinate, reducing the risk of yield loss. The team successfully eliminated all identified populations of pigweed, waterhemp, and foxtail. The farmer also highlighted the long-term benefits: reduced weed seed bank and lower weed pressure in subsequent seasons.
Insight from our client: Brillhart Farms
“The results we achieved with the Agremo platform are truly impressive. We were amazed by its ability to detect weeds even within dense soybean canopies (green-on-green scenario). This feature allowed us to spray only where it was truly needed. We will continue using Agremo next season for precision mapping and targeted spraying. It clearly delivers significant cost savings and protects our crop yield.”
– Dean S., Aerospace Structural Design Engineer, Brillhart Farms
